73

WORKING PARTY ON POPLAR AND WILLOW PRODUCTION SYSTEMS

74

75

ENDOGENOUS FACTORS AFFECTING ROOTING OF POPULUS SPECIES

A.M.A. Abd El-Dayem1, A.M. Sarhan, M.A. Darwesh, M.I. Saied Ahmed

This study was conducted at the nursery and laboratory of the Forestry Department, Horticultural Research Institute (HRI), Agriculture Research Center at Giza, Cairo, during the two seasons of 2000 and 2001. The aim was to improve vegetative propagation and study the behaviour of endogenous hormones during the growing season to define the optimal date for stem cutting preparation for planting, and overcome the problem of non-flowering of poplar species under Egyptian environmental conditions.

The results obtained indicated that endogenous hormones of the three studied Populus

species differed according to species and season as the lowest values of indole ascetic acid (IAA) were found in Populus nigra followed by P. alba and the maximum values were found in P. euramericana. On the other hand, abcissic acid (ABA) was at the maximum values in P. alba

followed by P. nigra and the lowest was in P. euramericana. Meanwhile, IAA reached the maximum values (mg/10gm fresh weight) during the period from 15 September to 15 December as the first order, while the second order was from 8 February to 1 March. Indole buteric acid (IBA) reached minimum values on 1 March, 15 November, and on 8 and 15 February for P. nigra. As for P. euramericana, IAA reached the maximum value on 22 February as the first order, and on 15 February, 1 March and from 15 October to 15 December as the second order. ABA reached the minimum values on 8 and 15 February. For P. alba, IAA was at the maximum value on 22 February. However, the lowest value of ABA was found on 1 March.

According to these results and from the practical planting dates usually followed in practice, P. nigra stem cuttings had an extended period for planting from 15 February to 8 March, while the best planting date for P. euramericana was 22 February, and for P. alba was from 15 to 22 February.

Key Words: vegetative propagation, Populus sp., endogenous hormones, non-flowering.

1 Forestry Department, Horticultural Research Institute (HRI), Cairo University, 9 Cairo University St. Orman, Giza, Egypt. E-mail: adayem_eg@hotmail.com

FAO ID 15

76

MULTIPLE BENEFITS OF WILLOW ENERGY CROPS

Lawrence P. Abrahamson1, Edwin H. White, Timothy A. Volk, Lawrence B. Smart

Willow energy crops are potentially renewable and sustainable. They provide biodiversity across the rural landscape, as well as protection and enhancement of soil and water attributes. They can produce electricity with no net addition of CO2 to the atmosphere, can play a significant role in a carbon-based economy, and maintain their productivity over multiple rotations while providing environmental and economic benefits to farming communities.

Willow’s perennial nature, rapid growth, root systems, and tolerance of high planting density make it ideal for phytoremediation, management of municipal waste-water and biosolids, living snowfences, riparian buffers, and alternative landfill covers. Willow production systems play a key role in recycling nutrients between rural and urban areas, and turning waste streams into valuable resources.

Key Words: Salix, short-rotation woody crops, biorefinery.

1 State University of New York, College of Environmental Science and Forestry, Syracuse, NY 13210, USA. E-mail: labrahamson@esf.edu

FAO ID 120

77

WEED CONTROL WITH HERBICIDES IN SALICACEAE PLANTATIONS OF BUENOS AIRES, ARGENTINA

Fabio Achinelli1, Alejandro Aparicio, Enrique Prada, Raúl Marlats

Common weed control treatments used by poplar (Populus spp.) and willow (Salix spp.) growers in Argentina are mechanical, in spite of their high cost, slowness, and high labour requirements. There are records worldwide of more than 60 herbicides used in Salicaceae, most of them tested in poplars. Although herbicides can suppress some of the drawbacks of mechanical control, active ingredients and dosis must be previously tested in each specific combination of site quality, weed community and clone. In this work we summarize and discuss the results obtained from the evaluation of 24 active ingredients of herbicides in poplar clones and six in American willow clone (Salix babylonica var. sacramenta) during the first two years post-planting in different sites of the humid pampas and the Parana River Delta, Buenos Aires, Argentina.

In poplar clones, a weed preemergence (PRE) or early weed post-emergence (ePOE) and poplar PRE treatment with outstanding control effectiveness, low cost and security consisted of 720 g ai.ha-1 of glyphosate in tank mix with 290 g ai.ha-1 of imazaquin; another promising treatment with the same mode of application consisted of 720 g ai.ha-1 of glyphosate mixed with 4 kg ai.ha-1 of atrazine. However, the use of atrazine as preemergent should be restricted to soils containing levels of clay and organic matter higher than 20% and 2.5% respectively. Treatments described above were complemented with spring and summer graminicide applications in weed and poplar POE: 68.04 g ai ha-1 of quizalofop-P-ethyl or 105 g ai.ha-1 of haloxyfop-R-methyl applications achieved good grass control without causing toxicity to poplars. Similar effects were obtained by applying 220 g ai.ha-1 of fenoxaprop-P-ethyl in a screening trial carried out in 2004. To control broadleaf weed escapes which are usual in these herbicide sequences, some tank mixes are being tested to be applied at mid spring: the combination of 105 g ai.ha-1 haloxyfop-R-methyl and 108 g ai.ha-1 of clopyralid applied in weed and poplar POE showed promising initial results. For American willow, weed and willow PRE treatments with good control levels and no phytotoxicity were 600 g ai.ha-1 of glyphosate mixed with 310 g ai.ha-1 of imazaquin or 91 g ai.ha-1 of isoxaflutole; haloxyfop-R-methyl and fenoxaprop-P-ethyl graminicides were applied in weed and willow POE at 113,4 g ai.ha-1 and 220 g ai.ha-1 respectively, without causing phytotoxicity.

Key Words: Populus, Salix, herbicides, plantations, Buenos Aires, Argentina.

1 Cátedra de Silvicultura, Facultad de Ciencias Agrarias y Forestales UNLP – Comisión de Investigaciones Científicas de la Provincia de Buenos Aires (CIC), CC 31, B1902WAA, La Plata, Buenos Aires, Argentina. E-mail: fachinel@ceres.agro.unlp.edu.ar

FAO ID 78

78

NEW HORIZONS OF NATURAL RESOURCES IN THE SOUTHEASTERN ANATOLIA REGION OF EURASIA AND THE

SOUTHEASTERN ANATOLIA PROJECT (GAP) IN TURKEY

Bulent Acma1

The Republic of Turkey has a special place in Eurasia in respect to both its socio-economic structure and its geo-politic and geo-strategic importance. It is also a model for the Islamic World combining traditional and modern life-styles.

The Southeastern Anatolia Project (GAP), one of the most important projects to develop the remarkable natural resources, is accepted as an opportunity to obtain benefits for some Eurasian countries from the quality water, forestry and agricultural resources of the Southeastern Anatolia Region.

The GAP Project has been considered as a regional development project over the years, but protection of the environment through forestry, agriculture and public participation has become the focus of the project in recent years. The GAP has the responsibility to undertake some important tasks and functions to improve fertility in the Islamic World and Eurasia in the future. In addition, the GAP will provide for improving water resources, forests and agricultural development in Eurasia.

The aim of this paper is to introduce this region with its rich natural resources and the GAP Project. The natural potential of the region is described first. Then, the GAP Project aiming to help the country use these natural resources is presented in detail. At the third stage, projects being implemented to protect the natural resources and environment are discussed. Finally, strategies and policies to develop and to protect particularly forestry in the region in the short, medium, and long term are proposed for Turkey and Eurasia.

Key Words: natural resources and environment, foresty, agricultural and water resources; Eurasia, Islamic World; Turkey; Southeastern Anatolia Region and GAP Project.

1 Anadolu University, Department of Economics, Unit of Southeastern Anatolia Project (GAP), 26470 Eskisehir, Turkey. E-mail: bacma@anadolu.edu.tr

FAO ID 137

79

INVENTORY OF BIODIVERSITY IN POPLAR STANDS IN THE PICARDIE REGION

Alain Berthelot1, Sylvie Augustin, José Godin, Guillaume Decocq

Biodiversity inventories were carried out in the Picardie region (in the north of France) on poplar plantations of various ages and situations. These inventories referred to three biological components: (i) ground-beetles, (ii) birds, (iii) vegetation.

For the ground-beetle study, some of the poplar stands could be compared with other border environments: cereal fields or broadleaved forests. The results showed that the specific richness of the poplar stands in the Picardie region varied according to sites but were overall high for the three components. The ground-beetle specific richness was very variable according to the studied sites, the highest being found on alluvial sites. The populations of ground-beetles seem to be structured according to soil moisture, vegetation cover and, to a lesser extent, soil pH. Differences were rarely significant. The comparisons carried out in 2003 with border environments indicated that specific richness in poplar stands is higher than in broadleaved forest and equivalent to that in cereal fields. The Shannon index and Equitability index (species distribution) were higher for poplar plantations and broadleaved forest. Ground-beetle populations in cereal fields were very unbalanced. The poplar stands seem able to accommodate species of open environments and forest species in balanced proportions.

For bird communities, poplar stands located on alluvial sites had higher specific richness and diversity than those located on the plateaux. Specific richness and diversity decreased with the age and canopy closure. The avifauna was primarily made up of ubiquitous species of closed forest environments. Species of open forest environments are more frequent in young poplar plantations without understorey. It seems there is no specific avifauna for poplar stands, except for Oriolus oriolus, which was very frequently observed.

Plant communities, in spite of the homogeneity of overstorey, were well diversified. The variety of sites, soils and previous vegetation could explain this diversity. This high specific richness could be due to suitable conditions (water and nutrient availability) of alluvial soils on which poplars are cultivated. The plant communities were structured by number and type of tendings (disks or mowing). The resulting disruptions tend to support the specific diversity, but, on the other hand, reduce the "phytosociological coherence" of the communities. The increase in available resources (light, water, nitrogen) benefited the cultivated poplars, but also sometimes the heliophilous social species (for example Rubus spp on plateaux) that compete strongly with other species.

Key Words: poplar, biodiversity, ground-beetle, bird, vegetation.

1 AFOCEL, Station Nord-Est, route de Bonnencontre, 21170 Charrey-sur-Saône, France. E-mail : alain.berthelot@afocel.fr

FAO ID 95

80

COMPARISON OF THREE COPPICE INTERVALS ON A NINE YEARS POPLAR BIOMASS PRODUCTION

Enrico Bonari1, Gianni Picchi, Alejandro Fraga, Marco Ginanni, Werther Guidi, Emiliano Piccioni

Hybrid poplars are the most promising trees for short rotation coppice (SRC) in Southern Europe; nevertheless, the cultivation technique for this genus has many not fully studied aspects. One of these is the proper harvesting interval (HI). HI length is important because it influences both the productivity and the vitality of the stumps. The HI also determines the diameter of the stools to be harvested, which is a key factor in harvest operations. In fact, stems with large diameters can be a limit for “cut and chip”-type machinery, requiring expensive forest harvesters, or even manual harvesting. The present research aims to compare three different intervals in terms of production, stump survival rate and diameters obtained from each treatment.

The experimental area is located in S. Piero a Grado (Pisa) in the Arno river valley, central Italy. The topography is flat and the soil type is a Typic Xerofluvent with good water availability for the poplars due to a superficial water table with a maximum depth in September of 1.2 m. The climate is Mediterranean with a yearly precipitation of about 900 mm, mostly distributed in spring and autumn.

Poplars (Populus deltoides var. Lux) were planted as 20 cm cuttings during the winter of 1996-1997 with a density of 10,000 per hectare. Three cutting intervals of 1 (T1), 2 (T2) and 3 (T3) years were adopted in three contiguous plots. In the winter of 2002-2003, all three treatments were harvested together for the first time, giving the opportunity to analyze in detail the response of the stools and to compare the three coppice intervals being tested. Variables recorded were diameter at 20, 70 and 120 cm above ground level, stem height, numbers of shoots per stool, stool survival rate, and biomass production at harvest.

The results show that there are statistically significant differences ( = 0.05) among all three treatments. T3 performs significantly better than the others with an average production of 21.7 tonnes of dry matter per year (t dm y-1) while T2 and T1 produced 16.3 and 10.7 t dm y-1

respectively. T3 produces stumps with a low number of stools but with a diameter in excess of 6 cm, a value often indicated as the upper limit for mechanical harvesting. So if many stools exceed this value they can represent a possible obstacle in harvesting operations.

Also T2 performs well, with lower stump mortality and a maximum stool diameter which allows mechanical harvesting with currently available cut and chip machinery. T1 has a low survival rate which is probably a result of the stress caused by the frequent stool cutting.

1 Land Lab, Scuola Superiore di Studi Universitari e di Perfezionamento Sant’Anna, Piazza Martiri della Libertà 33, 56127 Pisa, Italy. E-mail: bonari@sssup.it

FAO ID 135

81

Results obtained from this trial will be implemented in the “CO2 fix model” in order to quantify the overall carbon sequestration of the different treatments.

Key Words: short rotation coppice, biomass production, bioenergy, coppice intervals, Populus

deltoides, carbon sequestration.

82

SEASONAL GROWTH OF POPULUS DELTOIDES CLONES IN THE DELTA OF THE PARANA RIVER, ARGENTINA

Estebán D. Borodowski1, Raúl O. Suárez

The objective of this work was to evaluate the seasonal growth of different clones of Populus

deltoides Marsh. in the lower Delta area of the Paraná River in Argentina (34°S, 58°W). Mean annual rainfall and temperature are 1021 mm and 16.5°C respectively. Seasonal growth was evaluated of:

test 1: three mature plantations of different clones of Populus deltoides Marsh. (cv. Stoneville 71, cv. Catfish 5 and cv. I 72/51) of the same age planted at the same density, measured over three years; test 2: two mature plantations of Populus deltoides Marsh. cv. Catfish 5 of the same age planted at two different densities, measured over five years; and commercial plantations which included many clones (cv. Stoneville 67, cv. Catfish 2, cv. I 72/51, cv. Australiano 129/60 and cv. 208/68) measured over one year.

Circumference at breast height (1.30 m) of 110 trees in each treatment in test 1 and 95 trees in each treatment in test 2 was measured at three month intervals (related to the beginning of each season). Circumferences at breast height, at one month intervals, were measured in the commercial plantations.

In test 1, higher increments occurred in the spring-summer period (92 to 99% of the total annual growth). This tendency increased as plantation development advanced. Catfish 5 and I 72/51 presented principally spring growth, ranging from 73 to 80% of the total annual growth. Stoneville 71 distributed its growth between spring and summer (59 vs. 40 % respectively) as mean of the three years of measurements.

In test 2, the individual growth was higher at low density than at high density (P<0.01), in all growing periods. The higher increments occurred in the spring-summer period (98% of the total annual growth), and especially in the spring season, varying from 60 to 96% of the total annual growth. This tendency increased as plantation development advanced and was higher in high density plantations compared with low density.

The information collected from many clones and the results from tests suggest two types of seasonal growth: spring growth, principally for cv. Catfish 2, cv. Catfish 5, cv. Australiano 129/60 cv. I 72/51, and 208/68; and spring-and-summer growth for cv. Stoneville 67 and cv. Stoneville 71, proportionally distributed.

All clones stopped growth in March (beginning of autumn) although they had green leaves for many months more. Under these study conditions the seasonal growth pattern was directly related to clone, plantation age and density. This knowledge allows planning of water management, disease and weed control, along with other silvicultural practices.

Key Words: Populus deltoides, seasonal growth, management, Delta, Paraná River, Argentina.

1 Cátedra de Dasonomía, Facultad de Agronomía, Universidad de Buenos Aires, Argentina. E-mail: borodows@mail.retina.ar

FAO ID 111

83

A STUDY OF POPLAR BIOMASS UTILIZATION AS A SOURCE OF FODDER

M. Calagari1, A. Modir-rahmati, F. Asadi, R. Ghasemi

Trees and shrubs can supply the necessary quantity and quality of feed for grazing livestock. They are effective insurance against seasonal feed shortages or the risk of drought. In this research, seven poplar clones with high productivity and high survival rates were selected for two experiments. The purpose of this study was to investigate the feed resources for animals. In the the first experiment, the productivity of one-year old plants of poplar clones was evaluated at three removal intervals. Estimation of biomass yield (leaf and edible branches) showed that the maximum biomass production was for P.x eura 561/41, P. x eura triplo and P.deltoides

missoriensis clones with 18.02, 17.65 and 16.64 t.ha-¹ respectively, with significant differences at the 1% level of probability.

In the second experiment, the nutritive value of poplar clones was measured. Leaf samples were removed at the beginning and middle of the growing season. Then edible forage samples were analyzed for concentration of crude protein (CP), crude fiber (CF), dry matter (DM), acid-detergent lignin (ADL), neutral-detergent fiber (NDF) and acid-detergent fiber (ADF). Crude protein value ranged from 7.9 to 10.5% with P.x eura triplo, P.x eura 561/41and P. nigra 42/78 clones showing higher CP than other clones. Crude fiber value ranged from 15.2 to 19.8% at the early growing season and P. euphratica and P.x eura triplo showed higher CF than others. ADL ranged from 7.2 to 8.5% at the beginning of the growing season, and from 6.9 to 9.0% at the middle of the growing season. NDF and ADF values also ranged from 30.9 to 35% and 22.2 to 25% respectively.

Key Words: poplar, forage production, nutritive value.

1 Research Institute of Forests and Rangelands, P.O. Box 13185-116 Tehran, Islamic Republic of Iran. E-mail: Calagari@rifr-ac.ir

FAO ID 16

84

POPLARS: PLANTING DENSITY IN MENDOZA, ARGENTINA

A.D. Calderón1, N.E. Riu, J.A. Bustamante, V.G. Settepani, S.A. Pérez

One of the most important considerations in establishing poplar plantations is the spacing, but in our region this is a subject of controversy and discussions. For this reason and in order to establish precise parameters, a trial of poplar spacing was established in Junín, Mendoza (at 653 m above sea level) with surface irrigation.

The following clones were tested: Populus euramericana, Guardi and Populus deltoides

Harvard, using as design a variant of circular Nelder and Moris plots. The tested densities ranged from 204 plants/ha to 1,111 plants/ha. The area for each plant was between 9 m2 and 49 m2.

Analyses were made of growth differences of poplars in response to different spacings and to determine whether there were differences in tree stem cross-section.

Annual measurements of diameter at breast height (DBH) were made in order to calculate the basal area - expressed in m2 - of each tested spacing. In the future, annual measurements will be made using wood calipers in two directions in order to evaluate whether there are different stem cross-sections related to different spacings.

Conclusions are still partial due to the young age of the trees, although it can already be observed that trees planted at wider spacings have higher basal area values.

Key Words: Populus euramericana, Populus deltoides, planting density, growth.

1Instituto Forestal – Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Alte Brown 500 Chacras de Coria (M5528AHB) Mendoza, Argentina. E-mail: dasonomia@fca.uncu.edu.ar

FAO ID 105

85

POPLARS: TREE GROWTH RING STUDIES AND SITE QUALITY

A.D. Calderón1, S. Pérez, F.A. Roig, N.E. Riu, J.A. Bustamante, V.G. Settepani, S. Campos

A trial was conducted in order to determine if there is any correlation between variables which determine the quality of a forest site (soil depth, texture, salinity, fertility, etc.) and the development of poplars, using growth ring analysis as the means of study.

The trial was conducted in El Capacho (San Carlos, Mendoza) and was carried out in a commercial poplar plantation in which two different sections were identified, one with good growth and another with less vigorous development. Wood samples were extracted with an increment borer and processed in the laboratory using standard dendrochronological techniques. Soil pits were also dug and soil samples were extracted from each section in order to determine site quality characteristics.

The preliminary analysis of growth rings shows significant differences between the two sites since the plantation was established, because of the increment on the good site was 18.95 mm and on the other was 12.49 mm. In the tenth year, the increment on the good site was 3.23 mm and 0.80 mm on the other.

In the plots with deep silty-loam soils, with a salinity of 3.5 dS.m-1, diameter and average height of trees were 0.25 m and 22.5 m respectively; the average annual volume growth was 34 m3/ha/year. In the parcels with less deep silty-loam soils, with the first 0.45 m compacted and salinity of 5.7 dS.m-1, diameter and average height were 0.12 m and 14.0 m respectively; the average annual growth was 4.98 m3/ha/year.

The results show the importance of soil and site selection in poplar forestry programs because it is possible to obtain better production rates in better quality soils.

Key Words: poplar sp., growth ring analysis, site quality, soils, production rate.

1Instituto Forestal, Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Alte Brown 500 Chacras de Coria (M5528AHB) Mendoza, Argentina. E-mail: dasonomia@fca.uncu.edu.ar

FAO ID 106

86

POPULUS SP.: TRIAL OF DIFFERENT PLANTING STOCK TYPES AND PLANTING SEASONS AT MENDOZA, ARGENTINA

A.D. Calderón1, N.E. Riu, J.A. Bustamante, V.G. Settepani, S.A. Pérez

A trial was undertaken to determine planting stock types and planting seasons most appropriate for the establishment of poplar plantations under the environmental conditions in Mendoza, using the following clones: Populus euramericana, Conti 12 and Populus deltoides

Harvard.

The following planting material was used: 1-year old bareroot dormant plants of 2.5 to 3 m in height (R1T1 plants); R1T0 plants cut back to 30 cm above soil level; and cuttings of 30 to 40 cm in length and 1.5 to 2.5 cm in diameter. Planting was carried out between 26 August and 2 September in spring, and between 27 May and 10 June in autumn.

Survival was recorded at the end of the first year, and measurements of diameter at breast height (DBH) and tree height were made at seven years in order to calculate the actual wood volume expressed in cubic meters per hectare.

The best result was for Conti 12 planted in autumn, using 1-year old bareroot dormant plants, or planted in spring using cuttings. The best result for Harvard was planting in spring using R1T0 plants.

Key Words: planting seasons, planting stock, Populus euramericana, Populus deltoides, wood volume.

1 Instituto Forestal, Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Alte Brown 500 Chacras de Coria (M5528AHB) Mendoza, Argentina. E-mail: dasonomia@fca.uncu.edu.ar

FAO ID 107

87

CHARACTERIZATION OF FORESTED SITES OF SALIX NIGRA 4 AND SALIX BABYLONICA X SALIX ALBA CV 131/27 IN THE LOW

DELTA OF THE PARANA RIVER (ARGENTINA)

E. Casaubon1, L. Gurini, G. Cueto, L. Gómez, M. Zanelli, G. Berrondo, A. González

The objective of this work aims at the identification of the environment and management conditions which determine different productivities of Salix nigra 4 and of Salix babylonica x

Salix alba cv 131/27, one of the more frequently planted willows in the Paraná River delta in the province of Buenos Aires (Argentina). The Delta embraces 20 percent of high lands called “albardón”, and 80 percent of low lands called “pajonal” where willows thrive. Environmental factors evaluated were the floristic community, the relief and soil factors and their relationships with the height of dominant trees, and the site productivity. The Salicaceae average yield increment for this region was estimated at 20-25 m³/ha/year.

The study for Salix nigra 4 was carried out in a 12 year-old commercial plantation with trees planted with a 3.15 x 2 m spacing. The plantation occupied a surface of 1 ha in an area protected by a perimetrical dike of the low Delta of the Paraná River. It was subdivided into 112 plots of 100 m2 each, and each plot did not have more than 16 trees. In each of the four areas defined by the land elevation, 16 soil samples were analysed and studied. Dominant and average trees were identified. Their total heights were measured as well as the land contour elevation reading pertaining to the dominant tree. In each sector, three trial pits were made and soils samples were taken.

The conclusion reached for the Salix nigra 4 are: low areas protected by a perimetrical dam, pertaining to the textural family, franco thin, franco coarse and muddy thin, with greater water availability during the plantation growing period, showed an average increment of 47.78 m³/ha per year, while in areas with stagnant water the increment was similar to the average yield increment for this region (25 m³/ha/year). In this commercial plantation Rubus spp. is associated with good sites, but Carex riparia is associated with those sites of less quality.

As regards Salix babylonica x S. alba cv 131/27, the study was carried out in a 14 year-old commercial plantation with trees planted with a 3 x 2.5 m spacing. The inventory was taken in two sectors of the plantation, one with a surface of 12,700 m2 (Sector 1) and the other with a surface of 10,600 m2 (Sector 2).

In Sector 1, 110 plots of 105 m2 each were delimited, while in Sector 2, only 92 plots were delimited. Each plot did not comprise more than 14 trees. Each sector had a different water management: Sector 1 was always more irrigated than Sector 2. As for the other study, dominant and average trees were identified. Their total heights were measured as well as the land contour

1 E.E.A. Delta del Paraná-INTA. C.C. 14, CP 2804. Campana. Buenos Aires. Argentina. E-mail: ecasaubon@utenet.com.ar

FAO ID 45-46

88

elevation reading pertaining to the dominant tree. In each sector, three trial pits were made and soils samples were taken.

The conclusion reached for the studied Salix babylonica x Salix alba 131/27 are as follows: low areas protected by a dam, with a superficial layer of argillaceous muddy texture and with greater water availability during the plantation growing period, showed a 21.8 m3/ha yield per year, while the areas of argillaceous texture in the first layer and low water availability had a 17.385 m3/ha yield per year. In this commercial plantation, Iris pseudacorus is associated with good sites, while Rubus spp is associated with low quality sites.

Key Words: site, Salix nigra 4, Salix babylonica x Salix alba 131/27, willow, Paraná River Delta, Argentina.

89

SPACING TRIAL IN RELATION TO DENDROMETRIC VALUES IN POPLAR PLOTS AT THE "POZO DE LAS AVISPAS" FOREST EXPERIMENT STATION, PROVINCE OF JUJUY, ARGENTINA

Alcira Chocovar1, Carlos Picchi

At the former "Pozo de las Avispas" Forest Experiment Station, located at 900m above sea level, in the vicinity of Coronel Arias, Province of Jujuy, Argentina, besides the introduction of several provenances of poplars and varieties of willows, a spacing trial of poplar was established over 13,000 m2 of flat land under irrigation.

Annual rainfall amounts to 760 mm (29.5") concentrated over 80% in summer season (December to April); average annual temperature is 19.2ºC (66.3ºF); absolute maximum temperature 42.3º (108ºF) and the minimum observed during the 1984-95 period was -4.1ºC (23.7ºF). Soil texture is sandy loam below 40 cm (1.3ft) and loamy-sandy-clay at surface; pH averages 6.2. Short periods of frosts occurred in June or July. During the hottest periods, poplars partially dropped their leaves as a consequence of water stress.

The spacing trial comprised eight different distances: 6x6m, 6x4m, 4x4m, 4x2m, 3x2m, 2x2m, 2x1m, and 1x1m. No thinning was conducted, and nine years after plantation all trees were measured. The basal area of 19.4m2 (209 ft2) was the value observed to be consistent with site quality; this was equivalent to a 2x2m spacing and survival was up to 76%. The height mean annual increment was 1.62m (5.3ft) and mean annual increment in volume was 15.7m3/ha(224 ft3/per acre). The largest yearly growth in diameter breast height was 2.7cm (1.06") at the spacing of 6x6m.

Key Words: poplars, silviculture, spacing, Province of Jujuy, Argentina. 1

1 Cátedra de Dasonomía, Facultad de Ciencias Agrarias, Universidad Nacional de Jujuy, Gdor. José Iturbe 290, Y4600 XBF, San Pablo de Reyes, Provincia de Jujuy, Argentina. E-mail: anechocovar@arnet.com.ar

FAO ID 69

90

TAPER EQUATION FOR POPULUS X EURAMERICANA CV I-214 CLONES IN TWO

PLANTATION STANDS, VI REGION, CHILE

Patricio Corvalán1, Pamela Alvárez

Poplar cultivation in Chile is particularly important for small properties located in Region VI, where plantations of Populus x euramericana cv I-214 exist. These are short-rotation coppice and their purpose is for sawing and pulping products.

In order to plan, buck and maximize harvest profits, it is essential to have good estimates of the diameters of commercial logs. In this study, selected stems were felled and bucked, and radial growth was measured at 3.2 m intervals along each stem. This was performed in two stands spaced at 3 x 3.5 m and 4 x 4 m. Stem profiles were m modelled to describe the shape changes along the stem. Comparing the two populations it is concluded that there was no significant differences between individual trees within a stand or between the two stands.

Small neiloid and conical terminal sections were observed; however, most of the stems were a large paraboloid in the middle.

Key Words: stem profile, Populus, diameter, equation, height, model.

1 Universidad de Chile. Facultad de Ciencias Forestales. Departamento de Manejo Forestal. Santiago, Chile. E-mail: pcorvala@uchile.cl.

FAO ID 130

91

COSTS COMPARISON OF DIFFERENT POPLAR (POPULUS SPP.) ESTABLISHMENT SYSTEMS FOR THE ARGENTINIAN HUMID

PAMPAS

Gerardo Denegri, Fabio Achinelli, Raúl Marlats1

Poplar (Populus spp.) reforestation in the Argentinian humid pampas is being carried out by means of planting techniques and tending based on mechanical and manual work. Recent investigations showed that it is possible to improve this traditional establishment system (TM) by replacing hand weeding with band applications of herbicides, simple disc cultivation instead of cross disc cultivation, and by introducing localised fertilizer application with urea (F). Complete chemical control (Ch) has also been tested as another alternative, since it would avoid stump removal and disc cultivation. This study analyses the impact of these alternative treatments on reforestation costs, in a macro-economic scenery with varying exchange rates, salaries and input expenses.

Establishment costs were calculated for the following systems: mechanical chemical (MCh) with band applications of herbicides and simple disc cultivation and complete chemical(Ch) with whole chemical weeding; variants of these systems were included in calculations: MCh and Ch with F (MCh + F and Ch + F respectively) and also TM as a check system. In the current economic scenario, MCh systems reach 18.1% greater height growth than TM on the second year of rotation, with total cost differences ranging from –7.7% to +6.7%, depending on which preemergent herbicide is applied; growth in Ch system is 31.1% higher than the one obtained with MCh, causing a 30.5% reduction of the establishment cost when compared to the cheapest MCh. Fertilization of MCh systems produces an average 25.5% growth increase and also a 9% cost increase; the same fertilization treatment applied to the Ch system increases 13.5% height growths and also raise costs 13%. With four year results from field trials, possible yield increments or rotation length reductions are highly uncertain to predict. At this stage it would be advisable to evaluate these systems by considering their establishment cost as the main parameter. In this context, the alternatives with highest impact on costs reduction are first the Ch system, followed by a MCh system with atrazine. Sensitivity analysis applied to total costs shows that labour has the greatest influence on TM system costs, whereas in the case of MCh and Ch systems, variation is mainly due to the effect of exchange rate over input expenses.

Key Words: establishment costs, herbicides, fertilizers, Populus, Argentina.

1 Cátedra de Silvicultura, Facultad de Ciencias Agrarias y Forestales, UNLP - Comisión de Investigaciones Científicas de la Provincia de Buenos Aires, CC 31, B1902WAA, La Plata, Buenos Aires, Argentina. E-mail: fachinel@ceres.agro.unlp.edu.ar

FAO ID 75

92

REPLACEMENT OF MORTALITY IN POPLAR PLANTATIONS

R.C. Dhiman1, J.N. Gandhi

Poplar is the most domesticated forest tree in North India. Farmers grow it on their farms in association with agricultural crops and especially target their inputs to promote growth and development of poplar because of better returns associated with sale of wood in locally established markets. In good years, each tree can earn up to Rs. 2,000 (US$43) or even more at farm site. Poplar farming has high economic impact and has transformed the rural economy in this region.

Poplar is generally planted in blocks of 400 to 500 trees/ha at a spacing of 5m x 5m, 5m x 4m, 7m x 3m, 8m x 3m. Growth is very fast, reaching an average height of 25-30m and diameter 25-30cm within a 6-8 year rotation.

Good farm management produces good poplar stands with high tree densities. However, 80% of the initial planting is retained through to full rotation age. Mortality of about 10% occurs in the first year, especially the months immediately after planting. About 10% mortality occurs from the second to the sixth year of growth. Mortality in poplar plantations is associated with several factors, including: clone type, silvicultural quality of entire transplants (ETP), preconditioning of ETP before planting, delay in planting, planting site and soil conditions, irrigation after planting, cultural operations, animal damage, wind and fire damage. Poplar is a strong, light demanding tree and ETPs underplanted in the second year or thereafter are not able to catch up with the rest of the trees and these suppressed saplings produce only firewood/ pulpwood which have low market value.

ETPs are planted in the winter months of January-February, leaves start appearing in March and signs of mortality in the form of non-sprouting, blackening of buds and their dropping and drying of bark start appearing in March–April of the same year. ETPs maintained in the gunny bags/sugarcane leaf tubes are placed in the freshly dug holes at spots of dried plants and the plants grow well thereafter. Second and third year mortality is replaced by transplanting plants of the same age. Alternatively saplings of the last row of the plantation on the extreme south direction are uprooted and planted at the spots of dead plants, and the entire uprooted row is planted with fresh ETPs. This row gets least affected by the rest of the plantation because of abundant sunlight available. In this way it is possible to maintain 95 to 100% stocking at harvesting age. Data is presented on the growth and development of suppressed, normally growing and transplanted plants.

Key Words: replacement, mortality, survival, growth.

1 Wimco Seedlings Limited, Rudrapur, U.S.Nagar, Uttaranchal, India. E-mail: gsp51971@yahoo.co.in

FAO ID 153

93

GROWTH RESPONSE OF HYBRID POPLAR TO DIFFERENT IRRIGATION LEVELS

Jake Eaton1

Potlatch farms manage 7,000 hectares (17,300 acres) of hybrid poplar plantations in northeast Oregon. The plantations are managed on a twelve-year rotation to produce primarily saw logs for the furniture, veneer, molding, and cabinetry markets. A significant amount of chips are also produced for paper and fiber board. Processing residues are sold into the bioenergy and composting markets.

The farm is irrigated with water pumped from the Columbia River and distributed to the fields with a pressurized main line system. The water is then delivered to the trees via drip irrigation. The drip irrigation system allows precise application of irrigation and fertilizer to meet tree needs.

Irrigation-related expenses, primarily the energy costs to pump water, are one of the most significant costs of production. Since the farm’s inception more than 10 years ago, research on tree water needs, irrigation scheduling, and irrigation efficiency has been ongoing. In 2001 an irrigation study was begun to determine what irrigation level would result in the greatest amount of wood production per level of irrigation. More water generally produces more wood, but at some point the increase in productivity becomes uneconomical as production costs rise beyond the value of the wood produced.

Buried sensors continuously monitor soil moisture levels in the different irrigation treatments and application rates are adjusted frequently. Age three results showed a 900% difference in average tree volume (m3) between the high treatment (100% field capacity) and the low treatment (60% field capacity). Average tree size in the high treatment at the end of the third year was 17 cm diameter at breast height and 14 meters in height. Four year results are reported here for tree productivity and the most economical irrigation level. Aspects of soil moisture sensor technology and irrigation scheduling will also be discussed.

Key Words: tree farm, hybrid poplar, drip irrigation, fertigation, soil moisture sensor.

1 Potlatch Corporation Hybrid Poplar Program, Manager Research and Environmental Management Systems, PO Box 38, Boardman, OR, USA. E-mail: Jake.Eaton@Potlatchcorp.com

FAO ID 23

94

THE FIBRE MORPHOLOGY VARIATION OF TRIPLOID CLONES OF POPULUS TOMENTOSA AND ITS SUPPOSED HARVESTING

AGE FOR PAPER INDUSTRY

Fan Yongming, Zhang Zhiyi1, Xie Yimin, Ren Dakai, Luo Yuanyuan, Wu Yuying, He Jing

Wood as a pulping material is playing more and more important roles. As a reaction to the shortage of forest resources, the combination of afforestation with manufacture of paper products has become a model way to ensure a reliable material resource for China’s paper industry. Triploid clones of Populus tomentosa Carr. have been taken as the dominant fast-growing wood species in China. In order to obtain further information about variation of its traits, the fibre morphology of this newly developed wood species as well as the supposed harvesting age for its application in the pulp and paper industry were investigated in this paper.

The results showed that, in the first few years of growth, the average fibre length across the section at breast height increased from about 0.8 to more than 1.0 mm, which was faster than it did in the later years when the increment was only about 0.2 mm, in the following seven years. The standard deviation of fibre length distribution across the section at breast height at the older tree age was higher than that in the young tree for it involved both the young fibre and the matured one. The fibre length distribution within the annual rings was more concentrated than across the section and was basically stable among the tested growth years, but it increased to a limited extent between the rings as the tree grew. The cloned poplar featured a small Runkel ratio value (less than 0.4 - generally about 0.3), and this ratio increased slightly until 4-5 years of age. With regard to the morphology feature, such as average fibre length and Runkle ratio, the technological harvesting age of the triploid clone of Populus tomentosa Carr. BL304 should be 4-5 years old, at which the traits of this species could meet the requirement for papermaking. It could also be predicted from the test results that extending te growing period in the short term would not cause obvious improvements in fibre characteristics.

The test results also showed that the width of the annual rings at breast height increased quickly for the first growth years and reached its peak at the fifth to seventh growth year; but the largest area of the annual rings, which indicates the wood volume grown annually, occurred at the seventh or eighth years, when the increment slows down. Considering the financial performance, the supposed harvesting age for the pulp and paper industry should be 7-10 years old.

Key Words: triploid clones of Populus tomentosa, fibre morphology, annual ring, harvesting age, paper industry.

1 Institute of Chinese White Poplar, Beijing Forestry University, Beijing 100083, P. R. China. E-mail: zhangzy@bjfu.edu.cn

FAO ID 43

95

INFLUENCE OF SOIL FERTILITY ON PRODUCTIVITY OF SOME BLACK POPLAR CLONES ON FLUVISOLS AND

HUMOFLUVISOLS IN THE MIDDLE DANUBE BASIN

Zoran Galic1, Petar Ivanisevic, Sasa Orlovic, Sasa Pekec

This paper presents the results of investigations of soil fertility and growth (volume and average volume increment) in multiclonal field tests of poplar clones -214, 618 and 450 on three soil systematic units in the Middle Danube Basin in the flood-protected part of the alluvial plain.

The study results showed that humofluvisols had the highest potential (content of silt + clay and humus) of all the soil systematic units studied. On average, the highest volume of two cultivars of eastern cottonwood and one cultivar of Euramerican poplar was reached on a loamy fluvisol. On this fluvisol type, the Euramerican poplar clone (I-214) produced the highest roundwood volume, while the eastern cottonwood clones (618 and 450) reached the highest volume on the humofluvisol.

Key Words: soil fertility, growth, fluvisol soils, black poplar clones.

1 University of Novi Sad, Faculty of Agriculture, Poplar Research Institute, Novi Sad, Serbia and Montenegro. E-mail: galic@polj.ns.ac.yu

FAO ID 100

96

EARLY STAND DEVELOPMENT, CARBON SEQUESTRATION AND WILDLIFE USE UNDER CONVENTIONAL VERSUS

INTENSIVE AFFORESTATION PRACTICES IN THE LOWER MISSISSIPPI ALLUVIAL VALLEY

Emile S. Gardiner1, John A. Stanturf, Paul B. Hamel, Theodor D. Leininger

Afforestation of former agricultural land in the Lower Mississippi Alluvial Valley has progressed at a rapid rate since the early 1990s, as over 200,000 hectares have been removed from agricultural production during this period. Because this afforestation effort is quite extensive, conventional afforestation practices in the region are generally of low intensity and provide for only rudimentary establishment of forest cover. This basic approach has generated a demand for alternative afforestation systems that target establishment of more complex plantations capable of accommodating various landowner objectives while restoring functional processes of bottomland hardwood ecosystems.

Comprehensive research was initiated on an afforestation system that involves initial establishment of the rapidly-growing native species eastern cottonwood (Populus deltoides Bartr. ex Marsh.), followed by enrichment of the plantation understory with Nuttall oak (Quercus

nuttallii Palm.). Attributes of this interplanting system that may catalyze restoration of functional processes earlier than conventional approaches include a quick accretion of vertical structure, development of an understory micro-environment favorable to regeneration of other bottomland species, and a rapid development of a forest canopy to initiate progression of the evapo-transpiration cycle and turnover of woody debris.

Experimental plantings of the cottonwood - Nuttall oak interplanting system were established as part of a large-scale experiment designed to evaluate progression of forest restoration following various afforestation practices on former agricultural land. This presentation will highlight the development of understory regeneration, carbon sequestration, winter bird use and small mammal use in interplanted cottonwood stands and stands established under conventional afforestation practices. Results through year 10 suggest that an afforestation system involving rapid establishment of forest cover with a fast-growing early successional species like eastern cottonwood, followed by understory enrichment with species of later-succession, can provide an alternative method of forest restoration on bottomland hardwood sites that may address various landowner objectives and provide several environmental benefits.

Key Words: forest restoration, bottomland hardwoods, LMAV.

1 USDA Forest Service, Southern Research Station, Center for Bottomland Hardwoods Research, Stoneville, MS 38776, USA, and Forestry Sciences Laboratory, Athens, GA 30602, USA. E-mail: egardiner@fs.fed.us, jstanturf@fs.fed.us, phamel@fs.fed.us, tleininger@fs.fed.us

FAO ID 67

97

JUVENILE GROWTH PATTERNS IN POPLAR CLONES (POPULUS SPP.) IN THE ARGENTINIAN HUMID PAMPAS

Ana Gennari1, Enrique Prada, Fabio Achinelli, Raúl Marlats

In the Argentinian humid pampas, there is an increasing extension of commercial poplar plantations (Populus spp.). New clones and silvicultural practices are being evaluated for their prospective use considering the productive conditions of this region. Specific knowledge on these new clones’ growth pattern characteristics is needed in order to obtain a profitable combination between new genetic material and practices. This information would help to fit the intensity and opportunity of application of cultural treatments to the specific requirements of each clone. In the present study, juvenile height growth patterns of a selected group of 15 poplar clones are described and compared, by considering bud-breaking moments, length of height growth period, determination of maximum height growth rates in that period, and time of height growth cessation with winter-bud formation.

Data was obtained from periodic observations of three comparative clone trials planted in two forest properties located in Alberti, Buenos Aires and Teodelina, Santa Fé, Argentina. Each trial includes eight Populus deltoides clones and seven Euroamerican hybrids (Populus x

euramericana) clones, placed in a randomised complete block design with three replications.

After an observation period of two years, a preliminary classification of clone growth patterns in two basic groups is proposed. P. deltoides clones had longer growing periods than Euroamerican hybrids, due to early bud-breaking and later winter-bud formation compared to the latter; likewise Euroamerican hybrids reached maximum height growth rates before P. deltoides

clones. Nevertheless different behaviours were observed within each group: P. deltoides cv. “A. 208/68” Delta (INTA) had the latest bud-breaking of all clones, whereas P. x euramericana cv.“A. 568/1 Castelar” growth pattern was very similar to P. deltoides. The existence of differences in growth patterns and the indeterminate character of vegetative growth in poplars indicate that it would be feasible to prescribe specific silvicultural treatments for each clone group.

Key Words: growth pattern, phenology, Populus, humid pampas, Argentina.

1 Facultad de Ciencias Agrarias y Forestales, UNLP, Comisión de Investigaciones Científicas de Buenos Aires (CIC), CC 31, La Plata, Buenos Aires, Argentina. E-mail: fachinel@ceres.agro.unlp.edu.ar.

FAO ID 76

98

PLANTING STOCK MANAGEMENT TO IMPROVE SURVIVAL AT PLANTING OF POPULUS DELTOIDES BARTR. EX MARSH.

CLONES OBTAINED IN ARGENTINA

Ana Gennari1, Enrique Prada, Fabio Achinelli, Pablo Vivas

Populus deltoides clones, mainly from the United States, Europe and Australia, are used in poplar plantations (Populus spp.) in the Paraná River Delta region and the humid pampas of Argentina. Clones obtained by the Agricultural Research National Center, INTA, Castelar have recently been incorporated. The most noticeable clones are P. deltoides cv. A 610/12 Castelar andP. deltoides cv. A 562/47 Castelar (due to their growth behaviour). Comparative field trials planted in two sites of the humid pampas region showed cuttings of these clones having low survival, the same being evident in the female progenitor of this material (P. deltoides cv.Australia 129/60). The aim of this work is to study the effects of different management practices and planting stock type on the survival of these clones, in order to define guidelines to improve their establishment survival in field conditions.

The trial was carried out in a forest property located in Alberti, Buenos Aires, Argentina (34°50’ SL, 60°30’WL, 55 m above sea level, 930 mm of annual average rainfall). Three main variables were included: planting date: 1 July, 20 July and 6 August; clones: P. deltoides cv.Australia 129/60, P. deltoides cv. A 610/12 and P. deltoides cv. A 562/47; and cutting type, check treatment (commercial grade), cutting selected with buds and cutting prepared with branch portions. The experiment was laid out in factorial array, with a split-plot randomised complete block design with three replications. Periodical records of cutting survival were carried out during the 2003–2004 growing season. Analysis of variance did not show significant differences between planting dates. On the other hand, a significant interaction on cutting survival was found between clone and cutting type factors, which indicates differences of clone behaviour in the different cutting preparation alternatives. The highest survival values were obtained in the treatment of cuttings with buds, while lowest values were recorded in the check treatment for all clones. Importance and convenience of intensifying a careful stock selection for these clone plantations at commercial scale are discussed.

Key Words: Populus deltoides, cuttings, survival, planting date, planting stock selection, Argentina.

1 Cátedra de Silvicultura, Fac. de Ciencias Agrarias y Forestales, UNLP – Comisión de Investigaciones Científicas de Buenos Aires, CC 31, B1902WAA, La Plata, Buenos Aires, Argentina. E-mail: fachinel@ceres.agro.unlp.edu.ar

FAO ID 77

99

THE FINANCIAL ANALYSIS OF POPLAR POPULUS NIGRA L. PLANTATIONS

Mohammad K. Hassan1, Salim H. Haji

Iraq produces a very small portion of its consumption of timber and depends heavily on imports to meet its market demand. For a long time, farmers in the Kurdistan region of Iraq have been growing Populus nigra in small lots on their farms. Over the past decade, poplar plantations have increased in that region. This paper aims to compare the financial return of the grower’s management regime with a scientifically sound management regime. There is no standard management regime followed by all poplar growers. In general, plantations are intensively managed; however, errors are committed in terms of using very close initial spacing, less than 1m x 0.5m, inefficient fertilizing, disease control and insect attacks, and using unsuitable sites. Usually rotation age set at seven years aimed at producing small poles which are more profitable to produce since stumpage prices are not dependent on diameter in local markets. Mean annual increment (m.a.i.) is estimated at 25 m3/ha/year. Input and output data were gathered by interviewing growers, whilst prevailing prices in local markets at the time of preparing this paper were used.

Despite the inefficient management practices, investors were making good profits under current management. Under 10% real discount rates, net present value per hectare (NPV), benefit cost ratio (B/C), and internal rate of return (IRR) were found to be ID 3,881,250 (approximately US$ 2,050), 1.352, and 17.25% respectively.

The proposed management regime assumed that all effective treatments were practiced efficiently as far as timing and intensity were concerned. It was assumed that initial spacing was 2x1 m, that there were two thinnings and that the final harvest was at age 5 years. It was assumed that the m.a.i was 40 m3/ha/year. The value of the NPV per hectare, B/C, and IRR were ID 9,044,700 (approx. US$4,780), 1.84, and 33.82% respectively. If the investment lifetime was extended to include three coppice rotations, the NPV and B/C for four rotations investment were much greater than those of a single rotation for both regimes, whilst internal rate of return was slightly less for both regimes, the reason being that a 4-rotation investment was a bigger project (required more capital) compared with a single rotation, and additionally differed in the lifetime of the two alternatives. To choose between one or four rotation alternatives, one had to treat them as mutually exclusive projects and analyze them as such. The values of NPV for this analysis were ID 177,450 (approx. US$94) and 393,870 (approx. US$210) for the first and the second regime respectively. This indicated that a 4-rotation investment was more profitable than a single rotation for both regimes. Maximum value for renting the land or purchasing it and still making a 10% internal rate of return for both regimes and both alternatives was also calculated.

Sensitivity analysis indicated that both investments remained profitable even when costs were increased by 20% or revenues were reduced by 10% and costs increased by 10%. For a single rotation investment, the break-even analysis revealed that the minimum productivity of

1 Department of Forestry, College of Agriculture, University of Dohuk, Iraq. E-mail: ashty02@yahoo.com

FAO ID 102

100

stands that allows investors break-even was 15.75 m3/ha/year and 14.5 m3/ha/year for the first and second regime respectively. For 4-rotation investment, these figures were reduced to 15.1 m3/ha and 14.2 m3/ha for the first and the second regimes respectively. These figures were very low compared with what was anticipated to be achieved. Hence, the risk element was considered very slim for this investment. For many reasons, if an economic analysis was carried out, the profit would be greater; however, no attempt was made to conduct this analysis. State institutions concerned with research, extension and administration of forest resources must cooperate to obtain the most from poplar plantations.

Key Words: Kurdistan, Populus nigra, investments, financial return.

101

CONTRIBUTION OF POPLARS AND WILLOWS TO SUSTAINABLE FORESTRY AND RURAL DEVELOPMENT

IN INDIA

R.P.S. Katwal1

In India, the term ‘poplar’ is used synonymously with Populus deltoides, an exotic species introduced from North America during the early 1950s. This species has ushered in a revolution in production forestry in the country and contributes substantially to rural economy and sustainable forestry. It is grown as an agroforestry crop in fertile irrigated agricultural lands in the plains of north-west India. Poplar trees are planted in various spatial arrangements with agricultural crops and they add up to about 60,000 ha equivalent of pure plantations of this species. Although loss in crop yield is noticed close to the trees, yet the overall productivity in the entire fields is increased. Poplar grows fast, attaining about 25 m height and 30 cm dbh in 6 to 8 years. The average m.a.i. of poplar plantations is 20 to 25 m3/ha/year.

Poplar is the major species behind the development of a vibrant plywood industry in north-west India. It is also used to a significant extent in the match industry. The waste wood is used for making paper or as fuel. Every year poplar in non-forest areas produces 1.20 million m3

of wood for making plywood. It is thus saving 43,000 ha natural forests or 13,500 ha forest plantations from felling every year to produce the same quantity of wood. Farmers are earning handsome profits from nursery as well as plantation activities. Profits to the tune of 38.8 per cent to 100.9 per cent of investments after one year, depending upon scale of operation, are reported from producing nursery stock. In plantations, benefit:cost ratios of 1.92:1 and 2.13:1 are reported with pure poplar and with poplar plus intercropping over a period of seven years.

However, the price of poplar wood has come down alarmingly in the local market during the past two years. The reasons for this are not clear but it has presently brought much of the planting activity of poplar to a standstill.

Six species of indigenous poplars also occur in the Indian Himalayas. They grow relatively slow and are not extensively planted. P. ciliata is an exception. The populations of P. alba and P. euphratica are very small and need to be conserved. There is scope for promoting indigenous poplars in afforestation programmes.

India is home to 27 species of Salix, but this genus occupies a very small area in the natural forests and plantations in India. The plantations mainly consist of exotic species viz. S. alba ssp. coerulea and S.alba ssp. alba: these species yield wood for making cricket bats. Among the indigenous species, S. tetrasperma is planted to a noticeable extent. Willows provide fodder and fuel, and their twigs, branches and stems are used for domestic purposes and cottage industries. Salix is also important for effecting soil conservation. There is a need for promoting conservation and planting of willows in India.

Key Words: agroforestry, productivity, plywood, P. deltoides, P. ciliata, P. alba, P. euphratica,

S. alba, S. tetrasperma, conservation.

1 Director-General, ICFRE, P.O. New Forest, Dehradun 248006, India. E-mail: katwalrps@icfre.org

FAO ID 35

102

HEIGHT AND DIAMETER GROWTH OF FOUR-YEAR OLD HYBRID POPLAR CLONES

Kevin Keary1, Michael Bulfin, Máirtín Mac Siúrtáin

Two clonal trials, consisting of nine poplar clones, were laid out in March 1996 at Kinsealy Research Centre, Co. Dublin and Ballinea, Co. Westmeath in Ireland. Each experiment had a randomized block design, consisting of nine clones or treatments replicated in five blocks. Each experimental plot consisted of a single clone of 16 trees. The total height (h) (cm), diameter at breast height (DBH) (cm) and diameter at a height of 30cm (d30) (mm) were measured for living trees in the autumn of 1999 after the fourth growing season.

The data were balanced to facilitate analysis. The 45 means for each variable in each trial were analyzed as a randomized block design using the two factor analysis of variance (ANOVA) without replication option in ExcelTM with a specified level of significance, , of 0.05. The ANOVA was used to test the treatment hypothesis that all nine poplar clone means for each variable came from the same population. The treatment hypotheses were rejected for each of the three response variables in both trials with over 99.9% confidence. Using StatisticaTM, Duncan’s multiple range test was then applied separately to the three response variables for both sites to identify between which pairs of clonal means real differences are most likely to occur. The nine clone means for each response variable were ranked and three groups of varying levels of significance and a non-significant group of clones were identified. These groups provide an objective basis for provisional selection of similar and dissimilar hybrid poplar clones with respect to each response variable.

The results for Kinsealy identified provisional groups of clones, which did not differ significantly from each other with respect to the three response variables but differed at least significantly from all other poplar clones. Four of the six best-performing clones at Kinsealy; Beaupre, Boelare, Hazendans and Hoogvorst, were P. deltoides x P. trichocarpa hybrids. Theresults for Ballinea clearly identified Boelare as the best-performing clone relative to the three response variables. The overall best-performing clone at both sites was the poplar hybrid clone Boelare after four growing seasons.

Key Words: clonal trials, hybrid poplars, selection.

1 Forest Service, Department of Agriculture and Food, Johnstown Castle, Co. Wexford, Ireland. E-mail: kevin.keary@agriculture.gov.ie

FAO ID 122

103

INFLUENCE OF SOURCES OF VARIATION ON ROOTING OF HARDWOOD CUTTINGS OF BLACK POPLAR

(SECTION AIGEIROS)

Branislav Kova evi 1, Savo Ron evi , Petar Ivaniševi

The survival of planting material in nursery production and in the establishment of plantations has a significant impact on the financial results. The contribution of genotype and its interactions to the total variance gives the basis for evaluation of the importance of breeding and cultivar-adjusted technology in solving this problem in nursery production of black poplar.

The experiments were established at the usual season (first half of April), with 14 genotypes of black poplar, over two years and on two sites. The percentage of cuttings with live shoots 30 (D30), 40 (D40) and 80 days (D80) after planting was recorded, as well as the percentage of cuttings surviving at the end of the growing season (SURV). As the basis for determining the contribution of studied sources of variation to the total variation (based on three-way ANOVA), the influence of genotype, site, year, their interactions and error on the variation in survival of cuttings was evaluated.

Some rooted cuttings, which had live shoots at the beginning of May failed to survive during May and June (especially for some genotypes of eastern cottonwood that did not root easily), but survival did not decrease significantly after the beginning of July. The contribution of genotype to the total variation was around 10%, while genotype x site and genotype x year interactions together contributed over 10% to total variation. The contribution of site to the variation in survival of cuttings, as well as the contribution of year, is about 20%. The highest contribution of site to the total variation was for the percentage of cuttings with live shoots 40 days after planting (30%), while for year as the source of variation, the highest contribution was for percentage of cuttings with live shoots 30 days after planting (30%). The influence of site x year and genotype x site x year was insignificant for variation in all studied parameters. The contribution of error was usually around 40%.

The strong influence of differences among sites and years suggests the dependence of cuttings survival on characteristics of soil, climate and hydrology of particular years. Thus, the significance of good soil characteristics and application of proper cultural measures in the spring, could contribute more significantly to the cuttings survival than the selection of genotypes which root easily. The improvement of rooting of cuttings is an important task in the breeding of black poplars, but the differences among genotypes should be also respected in designing cultivar-adjusted technology.

Key Words: black poplars, hardwood cuttings, cutting's survival, sources of variation.

1 Poplar and Extraforestal Research Institute, Faculty of Agriculture, University of Novi Sad, Antona ehova 13, Novi Sad, Serbia and Montenegro. E-mail: branek@polj.ns.ac.yu

FAO ID 93

104

GROWING POPLARS IN PRIVATE FARM FORESTRYIN INDIA: SUSTAINABILITY ISSUES

Gulshan Kumar1

Poplars are amongst the world's fastest-growing industrial tree species, which can be grown as pure or mixed plantations as well as in association with agricultural crops. Market economics on the one hand, and increasing demand for industrial raw material of wood-based industries in India on the other, have compulsorily set a trend for raising fast-growing species like poplars. It is estimated that the current consumption of raw material by wood-based industries is between 24 and 30 million m3 annually, and is likely to increase several-fold in coming years. With land becoming a scarce resource, judicious land management systems have fast emerged on the farm scene with poplar occupying center stage along with agricultural crops. Poplar trees become ready for commercial exploitation within 6 to 8 years. Poplar wood is used for manufacturing veneer, plywood, matchboxes, fibreboard, sports goods, paper-pulp and packing cases.

In an effort to maximize returns from their farms, many enterprising farmers in India have been trying various combinations of tree species with agricultural crops. The success of growing poplars under agro-forestry models, particularly in the states of Punjab, Haryana and Western Uttar Pradesh, in the northern part of India, has created an annual wood market worth Rs. 15,000 million (US$ 323 million). But of late, an important question about the sustainability of this species under farm forestry has been unresolved due to decline in market prices for poplar wood. For the time being, the reasons for decline look temporary, but suitable steps are urgently required to control the damage and sustain the million-dollar market which flourished on this species. That will also determine the future of this important agro-forestry species in India.

This paper analyses the growth and decline of poplar in India, particularly in the northern states, where in the past farmers have grown it so widely. The role of private companies like WIMCO (Western India Match Wood Company) in promoting this farm forestry species has also been studied and is presented. The linkages between the industry and farmers have been critically analyzed and the reasons behind the decline of this species due to inadequate market support and other reasons have been thoroughly examined. Suggestions have been made to ensure good economic returns to farmers through a sound market-support system, corrective policy decisions and strong administrative measures to ensure the sustainability of poplars on farm lands. A healthy buyer-seller linkage has been envisaged for development of a “Sustainable Agro-Forestry-Industrial Model”.

Key Words: agroforestry, industry-farmer linkage, sustainability, market support system.

1 Gulshan Kumar, Indian Forest Service, Department of Forests, Haryana State, C-18 Van Bhawan, Sector-6, Panchkula, India. E-mail: cfhq@sify.com

FAO ID 138

105

FROM LIVING WALLS TO WOOD PANELS: MULTIPLE USES OF WILLOW STEMS PRODUCED IN SHORT ROTATION CULTURE

IN SOUTHERN QUEBEC, CANADA

M. Labrecque1, T.I. Teodorescu

Years of research on short-rotation woody crops using willow clones were conducted in Southern Quebec (Canada). The goal was to increase yields by improving cultural techniques, to identify better performing clones and to minimize production costs. Yield and productivity were studied over a number of years and according to various treatments such as soil characteristics, wastewater sludge fertilization and harvesting cycle time. It was demonstrated that under favourable conditions, yields of 20 to 25 oven dry tonnes of biomass per hectare can be obtained and maintained over years.

Formerly established for bioenergy purposes, it seems that willow stems produced under short rotation culture would now appeal to new markets. Recent studies highlighted the potential of the wood of willow for the manufacture of MDF and particle boards (medium density fibreboard). Industrial tests have shown that a significant percentage of willow branches including their bark could be used in a mixture with conventional material to produce wood panels conforming to very high quality standards.

Willows were also used in phytoremediation projects and their performance was shown to be superior to many other hyper-accumulating plant species grown on the same polluted urban sites. Pilot studies using willow stems in the construction of living noise-barriers were also conducted in different municipalities around Montreal (Quebec). These studies showed that “living walls” constitute an aesthetic and ecological solution to attenuate noise, are resistant to Quebec’s climatic conditions and benefit from a very high degree of social acceptability. These recent developments could influence the development of regional economic activities for the production of willows.

Key Words: willow, biomass crop, wood panel, living noise-barriers.

1 Institut de recherche en biologie végétale – Jardin botanique de Montréal, 4101 Sherbrooke East, Montreal, Que., H1X 2B2, Canada. E-mail : michel_labrecque@ville.montreal.qc.ca

FAO ID 132

106

THE ROLE OF CALCIUM AND CALMODULIN IN FREEZING-ACCLIMATION-INDUCED FREEZING RESISTANCE OF

POPULUS TOMENTOSA CUTTINGS

Lin Shanzhi, Zhang Zhiyi1, Lin Yuanzhen, Zhang Qian, Guo Huan

Populus tomentosa cuttings were taken from dormant branches collected from Heilongjiang Province, China. To explore the role of the calcium-calmodulin messenger system in the transduction of low temperature signals in woody plants, Populus tomentosa cuttings, after being treated with CaCl2 (10mmol/L), Ca2+ chelator EGTA (3mmol/L), Ca2+ channel inhibitor LaCl3 (100 mol/L) or CaM antagonist CPZ (50 mol/L), were used for freezing acclimation at -3 oC. The changes in the calmodulin (CaM) and malonaldehyde (MDA) contents, the activities of superoxide dismutase (SOD), peroxides (POD) and Ca2+-dependent adenosinetriphosphatase (Ca2+-ATPase) of mitochondrial membrane, as well as freezing resistance (expressed as LT50) of cuttings were investigated to elucidate the physiological mechanisms by which trees adapt to freezing.

The results showed that freezing acclimation increased the CaM content, the activities of SOD, POD and Ca2+-ATPase of the mitochondrial membrane as well as freezing resistance of cuttings, and decreased the MDA content as compared with control cuttings. Treatment with CaCl2 at the time of freezing acclimation enhanced the effect of freezing acclimation on the above-mentioned indexes, but this enhancement was abolished by Ca2+chelator EGTA, Ca2+

channel inhibitor LaCl3 or CaM antagonist CPZ, indicating that the calcium-calmodulin messenger system was involved in the course of freezing resistance development. The presence of CaCl2 at the same time as freezing acclimation also reduced the degree of decline in CaM content, and in SOD, POD and Ca2+-ATPase activities caused by freezing stress at -14 ºC, and enhanced the level of increase in CaM content, and in SOD, POD and Ca2+-ATPase activity in the recovery periods at 25 ºC. The change in CaM content was found to be closely correlated to the levels of SOD, POD and Ca2+-ATPase, and to the degree of freezing resistance of cuttings during freezing acclimation either with or without CaCl2 treatment.

It was suggested that the increase of CaM content induced by CaCl2 treatment promotes the formation of Ca2+-CaM complexes, which effectively activates the activities of SOD, POD and mitochondrial Ca2+-ATPase and then further results in the adaptive changes associated with the development and enhancement of freezing resistance. Thus, it could be concluded that Ca2+-calmodulin may be involved in the regulation of the increase in SOD, POD and Ca2+-ATPase activities, and the induction of freezing resistance of cuttings.

Key Words: Populus tomentosa cuttings, freezing acclimation, calmodulin, CaCl2, freezing resistance.

1 Institute of Chinese White Poplar, Beijing Forestry University, Beijing 100083, P. R. China. E-mail: zhangzy@bjfu.edu.cn

FAO ID 36

107

POPLAR AND WILLOW DEVELOPMENT AND USE IN NEW ZEALAND

Ian McIvor1, Sarah Hurst, John Charles, Lindsay Fung

The earliest introduction of poplar and willow species to New Zealand was P. nigra and S. babylonica with the arrival of English and French settlers in the 1840’s. In the following decades immigration was rapid, and land-hungry settlers burnt off heavily forested hills to develop pastoral farming. New Zealand is geologically young and has periods of high rainfall. The removal of forest exposed the landscape to severe erosion. Poplars and willows have subsequently been planted during the last 40 years as vegetative poles in large numbers to retain valuable topsoil and maintain sustainable rural development in hill country in the North Island.

A poplar and willow breeding programme began in 1968, but the arrival of Melampsora

rusts in the 1970’s gave impetus to scale up breeding efforts. Breeding has focussed on conservation qualities; wind, frost and drought tolerance, disease resistance, rough bark, poor opossum palatability and good form.

The degree of conservation planting has been strongly influenced in the past by subsidies from local authorities. More recently this assistance has been removed with a subsequent decline in planting. Information will be given on the development of the breeding programme, and the impact changing national policy on structuring and funding of science has had on the breeding programme.

The arrival of the willow sawfly Nematus oligospilus in 1997 has emphasised the need to maintain a vibrant breeding and research programme. The impact of this pest on tree willow plantings, the subsequent involvement of local authorities in the breeding programme and the research response will be discussed.

Other more recent exploratory uses of rural conservation plantings will be reported, including the role of poplar and willow for shelter, fodder, dairy effluent management and in animal health. These multiple end-uses of poplars and willows all require trees with different characteristics, and the breeding programme has been adapted to ensure that it can maximise the potential environmental and commercial benefits of new end-uses.

Key Words: breeding programme, breeding adaptability, soil conservation, New Zealand, rural use of poplar and willow, disease.

1 HortResearch, Private Bag 11 030, Palmerston North, New Zealand. E-mail: imcivor@hortresearch.co.nz.

FAO ID 82

108

ASPEN CAN BE CONSERVED BY CHANGES IN SILVICULTURAL PRACTICES IN BELGIUM

Patrick Mertens1

Black poplar populations underwent repeated regressions because of geological climatic changes, but also because of a severe reduction of its natural multiplication habitats caused by human domination on alluvial lands. Other reasons contributed to Aspen’s regression in spite of the discrete position it had in our region.

Whereas it propagates “like a weed” in the north of the American continent, its area was reduced by 50 to 60 % in the south part of Belgium between 1980 and 2000. The few broadleaf stands that still include aspen groups are mainly mixed and old. Aspens have regenerated only in certain open areas.

This species, considered “as having no economic interest”, is left aside by foresters “where trees do not disturb”, and where no treatment has been applied for two decades. Moreover, in the traditional broadleaf forests, the rare remaining old trees are often thinned.

This situation was analysed to open up sufficient new areas to regenerate aspens in our woodlands. The first result of this study is the total absence of local markets for its wood, the available volume being too limited to attract buyers and develop its specific processing. It could be used elsewhere, in particular in paper - and OSB panel - mills. As regards this regional analysis, the aspen biomass energy production seems most interesting to emphasise.

The second cause of the absence of aspen regeneration is silvicultural. Practices of progressive timber stand improvement and ageing forests are not adapted to the dynamic multiplication of a sun-seeking species as the pioneer aspen. The greatest practice of regeneration of shade species and the ecological pressure against the clear cuts have radically reduced aspen propagation and conservation.

With a reduced area of less than 3,200 hectares of mixed and ageing forest including aspen, new conservation management proposals have to be envisaged for conservation goals. Two particular site conditions are favoured: lands of abandoned cultures, and former spruce stands with low productivity. This activity should be carried out within the framework of site management for biological interest promulgated by the European Programme “Natura 2000”. In parallel the energy valorisation of aspen should be studied.

Key Words : Aspen, threatened species, regeneration of pioneers.

1 Attaché scientifique, C.R.N.F.B.-D.G.R.N.E.-M.R.W., Avenue du Maréchal Juin, 23 – 5030 Gembloux, Belgium. E-mail : P.MERTENS@MRW.WALLOMIE.BE

FAO ID 74

109

SOCIAL, ECONOMICAL AND ECOLOGICAL RESILIENCY AS MAJOR FACTORS FOR POPLAR CULTURE SUSTAINABILITY

Patrick Mertens1

In France, Italy and Belgium, where the poplar growers are well represented in Western Europe, the wooded land properties are often small and private, especially in the case of poplar groves. They come from abandoned arable lands. The timber harvested is somewhat grouped but not much. The market circumstance is unfavourable for the owner (producers) who cannot practically optimise his sale’s situation. Their isolated sale actions do not make up a sufficient force of decision within the increasingly industrialised valorisation system and, within the local organisation system that could act in favour of the owners.

The local authorities define the framework of the rural development in which the production of poplar can be regarded as very autonomous from the financial point of view. In fact the political authorities influence and establish the limits and uses of the land. In this way, the land price, the harvesting conditions, the level and the type of development of the inhabited rural zones are overall defined. The standard of rural living, at regional level in certain cases, can in its turn, be profitable to the decided political developments, by the economic contributions (local taxes and employment) and by the environmental advantages they generate. In this socio-economical sense, the poplar culture of our rural areas is related to the quality of life. At medium term, the social, economic and ecological factors must lead to the necessary creation of a sustainable framework for the poplar wood production. If not, it will be abandoned.

The resiliency analysis of the poplar production system is appealing to develop. This concept is derived from wood technology science, and expresses the capacity to resist the changes that the social-economical and ecological contexts lead to support. Some key elements are: a price becoming too high to buy the suited poplar production land or wood selling prices which do not remunerate the production cost and which can cause its stop and a substitution by other activities, or even a sale of the land. On the other hand, keeping the same price for the quality wood timber, can support the wood offer system. However, it must be sufficient to answer the total demand.

The local policy must ensure sustainable and favourable production conditions to poplar owners, by local and regional regulations which facilitate all the production stages, by reducing the income taxes, by limiting the harvesting constraints and the administrative tasks linked to the authorisation for aforestation and hunting. There is also a necessary informative dimension that the local authorities can support (local newspapers), by informing the inhabitants of the ecological and landscape benefit of these rural groves. Finally, at the infrastructure level, the opening of access roads to the hemmed plantations can be of important help, while promoting green walks near these ecological groves and making the harvesting conditions less expensive

So in Western Europe, the poplar production can remain resilient by direct and indirect support of competitive prices and a recognition of its ecological functions, remunerated by

1 Attaché scientifique C.R.N.F.B. – D.G.R.N.E. – M.R.W. Av. Maréchal Juin 23, 5030 Gembloux, Belgium. E-mail : P.Mertens@mrw.wallonie.be

FAO ID 71

110

organisational advantages. It is within this global framework that the poplar production of our countries took the form that we know today. It will be specified and developed in the presentation of this analysis.

Key Words : growers, policy, sustainability, marked conditions.

111

SEVEN YEARS OF POPLAR RESPONSE TO DIFFERENT IRRIGATION REGIMES

N.E. Riu1, V.C. Sanjurjo, J.A. Bustamante, A.D. Calderón

Over a three-year period an irrigation trial was conducted on seven-year old trees (Populus euramericana I-214) in Rivadavia Department (Mendoza). The soil had a deep sandy-loam texture. The trial was established in randomized blocks with four replications. The area of the trial was 192 m² with 20 trees in total. The irrigation intervals (IR) were 7, 14 and 21 days.

Results show that for IR = 7 days real evapotranspiration (Etc) was 2.091 mm; for IR = 14, Etc was 1,549 mm; and for IR = 21 Etc was 1,080 mm. Crop Coefficients (Kc) calculated using the Blanney and Criddle formula and from pan evaporimeter data were: Kc = 2.99 and 1.86 respectively for IR = 7 days; Kc = 2.22 and 1.39 for IR = 14; and Kc = 1.54 and 0.95 for IR = 21.

Wood production was: 122 m3/ha, 70 m3/ha and 47 m3/ha for IR = 7, 14 and 21 days respectively.

Statistical analysis showed that IR = 7 days was the best for seven-year old poplars, the annual irrigation number was 22 and the daily evapotranspiration was 14.6 mm/day.

Key Words : poplar, irrigation, evapotranspiration, crop coefficients.

1Instituto Forestal, Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Alte Brown 500 Chacras de Coria (M5528AHB) Mendoza, Argentina. E-mail: dasonomia@fca.uncu.edu.ar

FAO ID 117

112

SIX YEARS OF POPLAR RESPONSE TO DIFFERENT IRRIGATION REGIMES

N.E. Riu1, V.G. Settepani

Over a three-year period an irrigation trial was conducted on six-year old trees (Populus

euramericana I-214) in Rivadavia Department (Mendoza). The soil had a deep sandy-loam texture. The trial was established in randomized blocks with four replications. The area of the trial was 192 m² with 20 trees in total. The irrigation intervals (IR) were 7, 14 and 21 days.

Results show that for IR = 7 days real evapotranspiration (Etc) was 2.097 mm; for IR = 14, Etc was 1,467 mm; and for IR = 21 Etc was 1,051 mm. Crop Coefficients (Kc) calculated using the Blanney and Criddle formula and from pan evaporimeter data were: Kc = 2.95 and 2.06 respectively for IR = 7 days; Kc = 2.07 and 1.45 for IR = 14; and Kc = 1.47 and 1.05 for IR = 21.

Wood production was: 107 m3/ha, 57 m3/ha and 45 m3/ha for IR = 7, 14 and 21 days respectively.

Statistical analysis showed that IR = 7 days was the best for six-year-old poplars, the annual irrigation number was 21 and the daily evapotranspiration was 14.6 mm/day.

Key Words: poplar, irrigation, evapotranspiration, crop coefficients.

1Instituto Forestal, Facultad de Ciencias Agrarias, Universidad Nacional de Cuyo, Alte Brown 500 Chacras de Coria (M5528AHB) Mendoza, Argentina. E-mail: dasonomia@fca.uncu.edu.ar

FAO ID 112

113

EFFECT OF IRRIGATION BY INDUSTRIAL SEWAGE WATER ON THE GROWTH OF TWO POPLAR SPECIES

M.R. Shedeed1, A.A. Mousa, N. S. Abo Tabel, A.M. Abd El-Dayem, H.A. Gharib

This investigation was carried out at the nursery of woody trees of the Horticulture Research Institute during two successive seasons: 1997-1998 and 1998-1999. The aim was to investigate the effect of sewage water on the growth of one-year old Populus nigra and Populus

alba seedlings, cultivated in pots 30 cm in diameter containing soil from Ramdan City near a pool of sewage water.

The treatments included plants which were divided into five groups. These groups were irrigated with a range from 100% tap water to 100% sewage water.

The results obtained could be summarized as follows: the high concentration of drainage water led to a significant decrease in vegetative growth (seedling height, seedling diameter, dry and fresh weight, number of leaves, dry and fresh weight of leaves, root length, fresh and dry weight of roots).

Chemical analysis of seedlings showed that high concentrations of sewage water led to high accumulation of heavy metals in seedlings, but P. alba was more capable of resisting irrigation by sewage water. It might be recommended therefore to plant P. alba in Ramdan City, near the sewage water pool.

Key Words: sewage water, Populus nigra, Populus alba, vegetative growth, heavy metals.

1 Ain Shams University, Horticulture Department, Cairo, Giza, Egypt. E-mail: adayem_eg@hotmail.com

FAO ID 10

114

METHODOLOGY FOR THE DETECTION OF SALT TOLERANCE DIFFERENCES AMONG P. ALBA L. CLONES USING

CHLOROPHYLL FLUORESCENCE AS A TOOL

Hortensia Sixto1, Ismael Aranda, Nuria Alba, José Manuel Grau

Populus alba L. grows over a wide range of sites in Spain and its high adaptability to stress conditions (drought and salinity) has created much interest in selection and conservation programs. It is also considered a very important species in riparian ecosystems.

Previous studies on P. alba under controlled salt conditions showed that this species was not only the most tolerant in relation to other poplars species but also demonstrated intraspecific variability.

This study for salt tolerance variation tested five P. alba native clones in a factorial design under controlled greenhouse conditions. Rooted cuttings were watered regularly with half strength Hewitt nutrient solution and two salt applications were made per week during 45 days. Doses were 0, 68 and 137 mM of NaCl. Eight replications were used for each treatment and clone combination. Clones previously tested, `I-214´ (P. x euramericana) and P. euphratica (origin: Syria), were used as sensitivity and tolerance controls respectively.

Sensitivity to salt conditions was assessed through two different parameters related to chlorophyll fluorescence: initial fluorescence (F0) and Fv/Fm ratio as a surrogate of maximal photochemical efficiency of PSII (Photosystem II). Five plants were randomly sampled per treatment and clone at three different times: at the beginning of the experiment (T1 = day 1), in the middle (T2 = day 22) and at the end (T3 = day 45). Measurements were carried out around 12:00 a.m. on plants previously adapted to darkness for 30 minutes. An injury index (%) was also evaluated at the end of the experiment, as the number of plants which exhibited symptoms of burn.

Both Fv/Fm and F0 allowed detection of significant differences between clones, demonstrating the method as a useful tool to measure salt damage sensitivity. However, F0

showed a higher correlation to injury index than Fv/Fm .

The use of non-invasive methods, such as the chlorophyll fluorescence, which do not destroy plants, has been shown to be a useful method to infer differences in the response of P. alba clones to salt stress.

Key Words: Populus alba, salinity tolerance, chlorophyll fluorescence, Fv/Fm , F0.

1 CIFOR-INIA, Crta de la Coruña Km. 7,5 28040 Madrid, Spain. E-mail: sixto@inia.es.

FAO ID 13

115

AGROFORESTRY WITH POPULUS IN CHILE

Alvaro Sotomayor1, Jaime Ulloa, Edison García

In Chile, the use of agroforestry with Populus sp., is an alternative for farmers, to allow them to diversify their products and to reduce risk. This practice, used in many countries in the world, especially in Asia and Africa, could be a good alternative for small- and medium-scale farmers in Regions VI to X of Chile.

Cultivation of poplars in Chile has been mainly in forest plantations, to obtain wood for timber, boards, matches and other products. Agroforestry is a new alternative whereby farmers can combine trees, livestock and agricultural crops.

Examples of silvopasture systems of land use are carried out, where poplars are grown with pasture and cattle, and Alley Cropping, where different crops like maize, beans and others are grown in alleys. The results of trials of these experiences show that, for a period of time - usually the first 7 to 10 years - crops and animals can be used with poplars. Beyond the end of the rotation, the trees cause shade that strongly competes with crops and pastures.

The management of these agroforestry systems must consider intensive management to reduce competition, above- and below-ground. Issues related to density of trees, thinning and pruning, plantation arrangement, species selection, watering, fertilizing, control of weeds, phytosanitary questions and other factors must be considered to improve the productivity of the system.

Key Words: agroforestry, Populus sp., silvopasture systems, intensive management.

1 Instituto Forestal, INFOR, Camino a Coronel, Kilómetro 7,5, Concepción, Chile. E-mail: asotomay@infor.cl

FAO ID 140

116

BENEFITING HUMANKIND THROUGH IMPROVED APPLICATION OF POPLAR RESEARCH AND TECHNOLOGY

Brian J. Stanton1

“He plants trees to benefit another generation.” - Caecilius Status 220 -168BC

We live in a world defined by tremendous scientific achievements. The well-being of future societies, we are told, will be divided between those who embrace and utilize the technology of scientific advances and those who do not. Specifically, economic prosperity will hinge on revolutionary advances in quantum mechanics, genomics, and computer science. Where previously an abundance of natural resources determined economic strength, prognosticators now point out that successful societies of the future will require mastery of technology born of such complex sciences.

While certainly compelling, this vision of the future overlooks the importance of those issues most closely tied to society's more basic needs: an adequate supply of food and fiber plus clean water, air, and soil. Germane to this is a new take on the thirty-year old green revolution: the need for grain varieties less dependent on intensive agronomic practices of mechanized cultivation, irrigation, fertilization, and pesticides due to declining energy resources, drought, and global warming. In this context, improvements in the science of poplar cultivation will assume a pivotal function, with benefits in agro-forestry, amelioration of soil and water quality, and efficient fiber and green energy feedstock production. While the outlook for fiber production does not approach some of the forecasted world food shortages, we ought, nonetheless, to redouble our efforts to secure the future of the world's forest and fiber resources, especially in view of poplar's vital and unique ecological role in forestalling desertification, reforesting degraded lands, restoring riparian habitats, and sequestering greenhouse gases. The successful pursuit of a holistic environmental approach to fiber production – much of which will be increasingly sited on land of marginal agricultural quality – will create sustainable, livable, and prosperous societies as much as any other science.

The science of poplar cultivation has a long and impressive history in meeting the many needs of humankind. In the Pacific Northwest and the North Central Region of the United States, hybridization and varietal selection coupled with refined farming practices have increased yields by 150% and more; continuing such scientific successes will be an imperative in the future of a green poplar revolution. Yet, while research has achieved advances, the application of new technologies has lagged behind. In developing countries, how to overcome this lag may lie in simply demonstrating the impact and advantage of applying novel research findings. Conversely, in countries with a far lengthier history of research application, the reluctance to adopt further advances oftentimes stems from a limited knowledge of the economic impact of implementing new technology with attendant environmental benefits.

1 Managing Director, Resource Management Group, GreenWood Resources, PO 5905, Portland, Or 97228, USA. Coordinator of IUFRO Poplar and Willow Genetics Working Party 2 August 2004. E-mail: bstanton@greenwoodresources.com

FAO ID 147

117

But no matter the level of program sophistication, researchers must aggressively educate practitioners to ensure that discoveries are coincident with the adoption of new technologies. Likewise we must proactively communicate with policy makers so that the fruits of our investigations and our view of a brighter future are not lost in the decisions made by those less familiar with the power of science and agronomy. Researchers must work more closely with societal leaders to craft agricultural and environmental policy. The issues of our times – globalization, genetic transformation, clonal propagation and monocultures, conservation of species, populations, and genetic variation, climate change, and a growing world population – all demand a strenuous advocacy by the world’s poplar specialists and scientists. There is no greater imperative for quality work and the expedient application of our labors. Conversely, managers and leaders must resist the temptation to focus on short-term solutions rather than long-term planning to identify and pursue complete resolutions to our production and environmental challenges.

The effective implementation of poplar research and technology would be furthered immeasurably by: (i) the formation of well organized research consortia of governments, industries, and universities, (ii) multidisciplinary research initiatives encompassing genetics, physiology, pathology, biotechnology, agronomy, and ecology, (iii) a broad base of stable, long-term funding, (iv) coordinated research approaches focused on yield enhancement, durable pest resistance, cost reduction, sustainable farming practices, and soil and water improvement, and (v) research that can be adopted with minimal regulatory review and/or constraints such as resource conservation (e.g. reduced tillage, drip irrigation) and integrated pest management systems.

Poplar research should feature an internationally agreed-upon commitment to economic analyses that incorporate fiber-production, environmental, and ecological benefits. Equally important is the enactment of a mechanism to fund poplar research in third world countries (e.g. proceeds derived from an integrated global emissions trading market.) that makes equivalent investments in technology transfer and the dissemination of knowledge. Finally, environmental amelioration regulations, green certification programs for plantation practices and products, and commodity and energy pricing policies also could be used to promote improved poplar-growing technologies.

Key Words: poplar cultivation, poplar research, applied technology, holistic environmental approaches.

118

THREE-YEAR GROWTH RESPONSE OF FOUR CLONES OF EASTERN COTTONWOOD (POPULUS DELTOIDES BARTR. EX

MARSH.) TO FERTIGATION

John A. Stanturf1, Dexter Bland, Lisa Samuelson,Theodor Leininger, Bryce Burke

Early growth response of four clones of eastern cottonwood (Populus deltoides Bartr. ex. Marsh) to augmented site resources was examined in a fertigation experiment. Three clones came from native populations along the Mississippi River (ST66, ST72, ST75) and one was from an east Texas population (S7C15); all four clones were used operationally in the Lower Mississippi Alluvial Valley. Five treatments were replicated three times in a completely randomized block experimental design with clones as subplots. Treatments included control, irrigation alone, fertilizer alone, irrigation plus fertilizer (fertigation), and extended season fertigation.

Added nutrients and water significantly increased stand volume and woody biomass accumulation after three growing seasons; responses at the individual tree level were similar. The four clones grew differently but there were no interactions between treatment and clone for stand-level volume and biomass. Oven-dry leafless biomass increased from about 21 tons ac-1 in the control to almost 29 tons ac-1 in the extended season treatment. Stand volume increased from 57.8 m3/ha (826.8 ft3 ac-1) in the control to 81.6 m3/ha (1,165.7 ft3 ac-1) in the extended season. Clone S7C-15 was the best performer and accumulated over 29 tons ac-1 in three years, significantly more biomass than ST-66 and ST-72.

Key Words: cottonwood, P. deltoides, fertigation, stand volume, wood biomass.

1USDA Forest Service, 320 Green Street, Athens, GA 30602. USA. E-mail: drdirt_ms@yahoo.com

FAO ID 59

119

POPLARS INTEGRATED WITH CATTLE IN AN ASSOCIATED AND SUSTAINABLE WAY

Raúl O. Suárez1

The purpose of afforestation with poplars in order to produce high quality wood (thinning, pruning), with industrial (peeling) and/or commercial destination (exportation) results in a long and sustainable process of at least 14/15 year rotation. Economical intermediate returns should, however, be considered in order that the afforestation results are not so onerous and long-waiting until the final cutting.

Consequently, during this intermediate period, it would be necessary to include other short-term productive activity which would permit returns and amortize the investment.

In this connexion, it would be interesting to integrate cattle breeding to afforestation, in a combination which would not be competitive, but sustainable and complementary to poplars and willows, in the alluvial lands of the Delta as well as in the continental area of the meadowland pampeana, as described in the paper.

Key Words: forestry and cattle breading integration, adding activities, complementary, not competitive, animal load, forage, dry material.

1 Ing. Agr., Proyecto Forestal de Desarrollo, Argentina. E-mail: rsuarez@fibertel.com.ar

FAO ID 92

120

PRODUCTIVITY DECLINE AND REDUCED SOIL NUTRIENT AVAILABILITY AFTER SEVERAL ROTATIONS IN INTENSIVELY MANAGED POPULUS EURAMERICANA PLANTATIONS IN THE

CENTRAL VALLEY OF CHILE

J. Toro1, A. Fernández, J. Ulloa, L. Villacura

Biomass and nutrient accumulation were compared between a first and a fourth rotation cycle for two highly productive poplar clones. The stands, established in a recent volcanic ash soil in the Central Valley of Chile, showed 2.7 times differences in total biomass and stem-wood production suggesting a productivity decline after four rotations of continuous cultivation.

Nutrient content analyses of biomass components suggest that nitrogen (N) could be the major limiting nutrient at the site. Phosphorus (P) and potassium (K) foliar nutrient concentrations, based on total biomass analyses, suggest that also P and K may become limiting due to continuous nutrient export from the site with tree harvesting. Nutrient accumulations for the highest productive first rotation stand reached 423 kg/ha of N, 38 kg/ha of P, 166 kg/ha of K, 750 kg/ha of Ca and 89 kg/ha of Mg.

Forest management practices should reduce large site nutrient exports by avoiding whole tree harvest, and removing branches and debarking on site at harvesting.

Key Words: poplars, soil productivity, fertilization, forest nutrition.

1 Universidad de Concepción, Facultad de Ciencias Forestales. Chile. E-mail: jtoro@udec.cl

FAO ID 165

121

SIMULATOR OF GROWTH FOR POPULUS

Oscar Santiago Vallejos Barra1

The SALICA simulator is a Visual Basic Application (VBA) developed to run in the Excel environment that allows the physical and economic quantification of plantations of Populus. SALICA presents six modules: (a) adjustment of functions, (b) financial evaluation, (c) database of sampling units, (d) database for taper equations, (e) estimation procedure and (f) simulation.

SALICA is flexible since a function is adjusted depending on the existing database on sampling units. This flexibility allows the further estimations and simulations. Also, the financial evaluation allows the analysis of multiple management regimes considering not only forest activities but also agricultural and cattle activities.

Key Words: software, simulation of growth.

1 University of Talca, 2 Norte 685, Talca, Chile. E-mail: ovallejo@utalca.cl

FAO ID 168

122

FERTILIZATION OF SHORT-ROTATION INTENSIVE-CULTURE (SRIC) HYBRID POPLAR PLANTATIONS IN SOUTHWESTERN

BRITISH COLUMBIA, CANADA

C. van Oosten1, L.M. Zabek

There is limited published data on long-term responses to fertilization with inorganic fertilizers of short-rotation intensive-culture hybrid poplar plantations – SRIC hybrid poplar – grown under non-irrigated conditions. SRIC hybrid poplar plantations are established and managed in southwestern British Columbia and the Prairie provinces of Canada, using agronomic methods. Fertilization has the potential to significantly increase yields.

In the spring of 1996, a series of hybrid poplar (Populus trichocarpa x P. deltoides)fertilization research trials was established on eastern Vancouver Island (British Columbia, Canada) in three 2-year old plantations (planted in 1994). Results in the fall of 1998 showed a positive response to fertilization with both nitrogen (N) and phosphorus (P) in early 1996 and a repeated fertilization of N in early 1997. Both times the fertilizer was broadcast into the stand. To determine if fertilization of SRIC hybrid poplar is a cost-effective tool to increase yield, the trials were remeasured in March 2004, eight growing seasons after the initial fertilization in 1996. At a plantation density of 1,100 trees per hectare, the plantation is forecast to reach culmination of mean annual increment between the 10th and 12th year.

At age 10, eight years after the initial fertilization, effects were still evident. In general, the volume index (basal area per tree x height) growth was greatest in response to P addition with N. Potassium (K) addition with N and P did not seem to provide any additional benefit for any of the hybrid poplar clonal varieties at any of the sites.

From an operational perspective the results indicate growth responses ranging from a low of 8% to a high of 88%, when using fertilizers containing N and P on medium to good sites. For analysis purposes, a substantially lower range of 8% to 39% was considered. Baldock and Burgess (1996) reported incremental increases in hybrid poplar fertilizer responses between 14% and 30% when banding rather than broadcasting the fertilizer. Due to the beneficial effect of banding fertilizer, as is also well documented in agriculture, the conservative range of growth responses was modified accordingly.

Financial results using a discounted cash flow method were reviewed and the Internal Rate of Return (IRR) for each option was calculated. As expected, the financial results are very sensitive to the selling price of the wood. Based on the range of fertilizer responses and financial results, fertilization of SRIC hybrid poplar on standard and good hybrid poplar sites makes financial sense.

The authors gratefully acknowledge the financial support provided by the Canadian Forest Service.

Key Words: poplar fertilization.

1 SilviConsult Woody Crops Technology Inc., Nanaimo, B.C., Canada. E-mail: silviconsult@telus.net

FAO ID 119

123

COMPARISON OF WILLOW GROWTH IN POT AND FIELD CONDITIONS UNDER VARIOUS TREATMENTS

M. Weih1, N.-E. Nordh

Short rotation forestry for the purpose of biomass production in Sweden has mainly focussed on the use of willow (Salix spp.). Willows constitute a relatively new crop and the potential for growth improvement is significant. Thus, new hybrid clones have the potential to grow considerably faster than the clones traditionally used in Swedish short rotation coppice. The results of previous research indicate that the growth-physiological characterization of young willows in the short term (several months) might comprise a suitable approach for the pre-selection of promising clones prior to extensive field evaluation. However, this preliminary conclusion strongly depends on the degree to which the results from the short-term pot study reflect the growth pattern of the clones seen in the field. The purpose of the current study was to test this assumption.

A short-term pot study was performed outdoors near Uppsala and included 14 different willow clones and four experimental treatments differing in the availability of water and nutrients. A field study involved the establishment of three willow plantations near Uppsala and on the Gotland island. These field plantations involved up to nine different clones and partly different irrigation and fertilization treatments. The biomass growth of the plants was followed both in the pot study and the field trials, and the results were compared.

It was concluded that differences in growth parameters between the clones and treatments in the three-month pot study closely reflect the growth performance in the field during the first and third year of growth, as well as the standing biomass after the first cutting cycle. The method developed here could facilitate the selection of appropriate plant material at a given site and contribute to improving the management and yield of Salix energy plantations.

Key Words: Salix spp, willow clones, biomass growth, irrigation, fertilizer.

1 Department of Short Rotation Forestry, Swedish University of Agricultural Sciences, P. O. Box 7016, SE-750 07 Uppsala, Sweden. E-mail: martin.weih@lto.slu.se

FAO ID 22

124