IR-4 Ornamental Horticulture Program Trial Report Researcher(s): Heiner Lieth, UC Davis PRNumber(s): 26165, 26166 1 Project Title: Evaluation of phytotoxicity of Sedgehammer (Halosulfuron) on Fraser Fir (Abies fraseri) and Douglas Fir (Pseudotsuga menziesii) Protocol #: 07-011 Report date: December 12, 2007 Authors: Heiner Lieth and Linda Dodge Department of Plant Sciences University of California, Davis Davis, CA 95616 Narrative Summary: Abies fraseri and Pseudotsuga menziesii plants growing in 1-gallon containers received two applications of Sedgehammer (Halosulfuron) at 0.047 lb ai/acre (1X), 0.094 lb ai/acre (2X) or 0.188 lb ai/acre (4X) rates as described in the Materials and Methods section of this report. The interval between applications was 4 weeks. The plants in the Control group received no Sedgehammer. The trial was conducted outdoors over 8 weeks from April 20, 2007 to June 14, 2007. Results and Discussion for Abies fraseri The Abies fraseri plants in the control group had phytotoxicity index levels near zero at all times including week 8 (Tables 1 and 5, Figures 1a and 1b). The first application of Sedgehammer resulted in no significantly higher levels of phytotoxicity for any of the dosage levels. Even up to week 6, all phytotoxicity levels in the trial were below 1, indicating no phytotoxicity. At week 8 there was a significant effect due to the herbicide. The mean phytotoxicity levels of the 1X and 2X treatments were 2.3 and 2.2 (not significantly different). The phytotoxicity level of the 4X treatment on week 8 was 4.6, significantly different from the 1X and 2X treatments. By week 8, the height and width increases in the control averaged 5.5 cm and 7.5 cm (Tables 1 and 5, Figure 3). The plants in the 1X treatment grew 4.4 cm and 5.6 cm in height and width respectively, translating into a significantly smaller volume index than for the control. Although it took well over 6 weeks from the first application, by week 8 a significant growth retardation and phytotoxicity effect was found when applying Sedgehammer over Abies fraseri. Thus Sedgehammer is not safe for Abies fraseri. Results and Discussion for Pseudotsuga menziesii The Pseudotsuga menziesii plants in the control and Sedgehammer treatments had phytotoxicity index levels below 1 during the first 4 weeks of the trial (Tables 2 and 6, Figures 2a and 2b). After the second application of Sedgehammer the phytotoxicity index levels were significantly greater than in the beginning. The phytotoxicity index increase of the 1X treatment was 1.9 at week 8, with levels rising with increasing dosage. The phytotoxicity index increase averaged 3.1 in the 4X treatment at week 8.
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IR-4 Ornamental Horticulture Program Trial Report
Researcher(s): Heiner Lieth, UC Davis PRNumber(s): 26165, 26166 1
Project Title: Evaluation of phytotoxicity of Sedgehammer (Halosulfuron) on Fraser Fir
(Abies fraseri) and Douglas Fir (Pseudotsuga menziesii)
Protocol #:
07-011
Report date:
December 12, 2007
Authors: Heiner Lieth and Linda Dodge Department of Plant Sciences University of California, Davis Davis, CA 95616
Narrative Summary: Abies fraseri and Pseudotsuga menziesii plants growing in 1-gallon containers received two applications of Sedgehammer (Halosulfuron) at 0.047 lb ai/acre (1X), 0.094 lb ai/acre (2X) or 0.188 lb ai/acre (4X) rates as described in the Materials and Methods section of this report. The interval between applications was 4 weeks. The plants in the Control group received no Sedgehammer. The trial was conducted outdoors over 8 weeks from April 20, 2007 to June 14, 2007. Results and Discussion for Abies fraseri The Abies fraseri plants in the control group had phytotoxicity index levels near zero at all times including week 8 (Tables 1 and 5, Figures 1a and 1b). The first application of Sedgehammer resulted in no significantly higher levels of phytotoxicity for any of the dosage levels. Even up to week 6, all phytotoxicity levels in the trial were below 1, indicating no phytotoxicity. At week 8 there was a significant effect due to the herbicide. The mean phytotoxicity levels of the 1X and 2X treatments were 2.3 and 2.2 (not significantly different). The phytotoxicity level of the 4X treatment on week 8 was 4.6, significantly different from the 1X and 2X treatments. By week 8, the height and width increases in the control averaged 5.5 cm and 7.5 cm (Tables 1 and 5, Figure 3). The plants in the 1X treatment grew 4.4 cm and 5.6 cm in height and width respectively, translating into a significantly smaller volume index than for the control. Although it took well over 6 weeks from the first application, by week 8 a significant growth retardation and phytotoxicity effect was found when applying Sedgehammer over Abies fraseri. Thus Sedgehammer is not safe for Abies fraseri. Results and Discussion for Pseudotsuga menziesii The Pseudotsuga menziesii plants in the control and Sedgehammer treatments had phytotoxicity index levels below 1 during the first 4 weeks of the trial (Tables 2 and 6, Figures 2a and 2b). After the second application of Sedgehammer the phytotoxicity index levels were significantly greater than in the beginning. The phytotoxicity index increase of the 1X treatment was 1.9 at week 8, with levels rising with increasing dosage. The phytotoxicity index increase averaged 3.1 in the 4X treatment at week 8.
IR-4 Ornamental Horticulture Program Trial Report
Researcher(s): Heiner Lieth, UC Davis PRNumber(s): 26165, 26166 2
By week 8, the height and width increases in the control averaged 12.4 cm and 11.8 cm, respectively (Tables 2 and 6, Figure 4). The plants in the 1X treatment grew only 3.8 cm and 6.8 cm in height and width, respectively, translating into a significantly smaller volume index than for the control. The volume index mean in the 1X treatment was 37% of the control. Significant growth retardation and phytotoxicity effects were found when applying Sedgehammer over Pseudotsuga menziesii. Thus Sedgehammer is not safe for Pseudotsuga menziesii.
IR-4 Ornamental Horticulture Program Trial Report
Researcher(s): Heiner Lieth, UC Davis PRNumber(s): 26165, 26166 3
Results Table Table 1. Phytotoxicity and growth changes over 8 weeks for Abies fraseri treated with 0 (Control), 0.047 (1X), 0.094 (2X) or 0.188 (4X) lb ai/acre Sedgehammer at weeks 0 and 4. Differing letters a, b, c… designate significant differences among the four means; "Yes" and "no" indicates whether there was an overall significant treatment effect at the 5% level (NA means no variation in data; "yes at 10%" means treatment effect was significant at 10% but not at the 5% level). Means ± SE (n=9) Phytotoxicity Effect of Sedgehammer on Abies Phytotoxicity Index Increase from beginning of trial until: Treatment 1 week (NA) 2 weeks (NA) 4 weeks (NA) 0X 0.00 ± 0.00 a 0.00 ± 0.00 a 0.00 ± 0.00 a 1X 0.00 ± 0.00 a 0.00 ± 0.00 a 0.00 ± 0.00 a 2X 0.00 ± 0.00 a 0.00 ± 0.00 a 0.00 ± 0.00 a 4X 0.00 ± 0.00 a 0.00 ± 0.00 a 0.00 ± 0.00 a Phytotoxicity Index increase from beginning of trial until: Treatment 5 weeks no 6 weeks no 8 week yes 0X 0.00 ± 0.00 a 0.00 ± 0.00 a 0.00 ± 0.00 c 1X 0.00 ± 0.00 a 0.11 ± 0.11 a 2.33 ± 0.37 b 2X 0.00 ± 0.00 a 0.00 ± 0.00 a 2.22 ± 0.60 b 4X 0.33 ± 0.33 a 0.56 ± 0.44 a 4.56 ± 0.71 a Growth Effect of Sedgehammer on Abies Increase by week 8 of:
Treatment Height (cm) yes Average Width
(cm) yes Volume Index yes
0X 5.50 ± 0.32 a 7.50 ± 0.47 a 4867.00 ± 640.05 a 1X 4.44 ± 0.60 ab 5.64 ± 0.77 b 2529.17 ± 605.48 b 2X 3.72 ± 0.42 b 5.00 ± 0.51 b 1994.28 ± 248.03 bc 4X 2.28 ± 0.60 c 2.61 ± 0.73 c 1067.21 ± 299.42 c
IR-4 Ornamental Horticulture Program Trial Report
Researcher(s): Heiner Lieth, UC Davis PRNumber(s): 26165, 26166 4
Table 2. Phytotoxicity and growth changes over 8 weeks for Pseudotsuga menziesii treated with 0 (Control), 0.047 (1X), 0.094 (2X) or 0.188 (4X) lb ai/acre Sedgehammer at weeks 0 and 4. Differing letters a, b, c… designate significant differences among the four means; "Yes" and "no" indicates whether there was an overall significant treatment effect at the 5% level (NA means no variation in data; "yes at 10%" means treatment effect was significant at 10% but not at the 5% level). Means ± SE (n=9) Phytotoxicity Effect of Sedgehammer on Pseudotsuga Phytotoxicity Index Increase from beginning of trial until: Treatment 1 week (NA) 2 weeks no 4 weeks no 0X 0.00 ± 0.00 a 0.33 ± 0.24 a 0.33 ± 0.24 a 1X 0.00 ± 0.00 a 0.11 ± 0.11 a 0.00 ± 0.00 a 2X 0.00 ± 0.00 a 0.00 ± 0.00 a 0.56 ± 0.24 a 4X 0.00 ± 0.00 a 0.11 ± 0.11 a 0.56 ± 0.34 a Phytotoxicity Index increase from beginning of trial until: Treatment 5 weeks yes 6 weeks yes 8 week yes 0X 0.78 ± 0.28 c 1.22 ± 0.32 bc 0.44 ± 0.24 c 1X 1.00 ± 0.33 bc 0.67 ± 0.33 c 1.89 ± 0.31 b 2X 1.89 ± 0.42 ab 1.89 ± 0.65 ab 2.44 ± 0.47 ab 4X 2.22 ± 0.36 a 2.78 ± 0.49 a 3.11 ± 0.42 a Growth Effect of Sedgehammer on Pseudotsuga Increase by week 8 of:
Treatment Height (cm) yes Average Width
(cm) yes Volume Index yes
0X 12.44 ± 1.32 a 11.78 ± 1.95 a 33339.6 ±7626.04 a 1X 3.83 ± 1.01 b 6.75 ± 1.06 b 12294.4 ±2587.47 b 2X 4.39 ± 0.93 b 6.36 ± 0.70 b 11307.3 ±2047.97 b 4X 2.33 ± 0.97 b 3.92 ± 0.88 b 5785.19 ±1536.99 b
IR-4 Ornamental Horticulture Program Trial Report
Researcher(s): Heiner Lieth, UC Davis PRNumber(s): 26165, 26166 5
0
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toto
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Control1X2X4X
Species: AbiesMaterial: Sedgehammer
Figure 1a. Phytotoxicity ratings for Abies fraseri plants exposed to two applications of 0 (Control), 0.047 (1X), 0.094 (2X) or 0.188 (4X) lb ai/acre Sedgehammer at weeks 0 and 4. See Table 3 for explanation of ratings.
Figure 1b. Phytotoxicity symptoms seen on Abies fraseri plants exposed to two applications of 1X (left) or 2X (right) Sedgehammer. Symptoms included shoot tip chlorosis and burning of shoot tips.
IR-4 Ornamental Horticulture Program Trial Report
Researcher(s): Heiner Lieth, UC Davis PRNumber(s): 26165, 26166 6
0
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Control1X2X4X
Species: PseudotsugaMaterial: Sedgehammer
Figure 2a. Phytotoxicity ratings for Pseudotsuga menziesii plants exposed to two applications of 0 (Control), 0.047 (1X), 0.094 (2X) or 0.188 (4X) lb ai/acre Sedgehammer at weeks 0 and 4. See Table 3 for explanation of ratings.
Figure 2b. Phytotoxicity symptoms seen on Pseudotsuga menziesii plants exposed to two applications of 1X (left) or 2X (right) Sedgehammer. Symptoms included shoot tip chlorosis and burning of shoot tips.
IR-4 Ornamental Horticulture Program Trial Report
Researcher(s): Heiner Lieth, UC Davis PRNumber(s): 26165, 26166 7
Block A
Block B
Block C CONTROL 1X 2X 4X Figure 3. Abies fraseri plants 8 weeks after two applications of 0 (Control), 0.047 (1X), 0.094 (2X) or 0.188 (4X) lb ai/acre Sedgehammer at weeks 0 and 4.
IR-4 Ornamental Horticulture Program Trial Report
Researcher(s): Heiner Lieth, UC Davis PRNumber(s): 26165, 26166 8
Block A
Block B
Block C CONTROL 1X 2X 4X Figure 4. Pseudotsuga menziesii plants 8 weeks after two applications of 0 (Control), 0.047 (1X), 0.094 (2X) or 0.188 (4X) lb ai/acre Sedgehammer at weeks 0 and 4.
IR-4 Ornamental Horticulture Program Trial Report
Researcher(s): Heiner Lieth, UC Davis PRNumber(s): 26165, 26166 9
Materials & Methods/Recordkeeping: Crop History
Crop Cultivar/Variety: Fraser Fir (Abies fraseri) and Douglas Fir (Pseudotsuga menziesii)
Date of Seedlings: Received from Weyerhaeuser 3/26/07 Date of Emergence: Date of Transplanting: 4/5/07 Potting Mix: UC Mix: 1/3 sand, 1/3 peat, 1/3 bark (by volume) Pot size & spacing: 1-gallon pots spaced on 12-inch centers Row spacing:
Product(s) applied prior to start of experiment:
Product Rate Application Type
Date of Application
Crop Growth Stage
Application Volume
Osmocote 15-9-12 1 tsp./pot Topdress 4/20/07 Actively growing NA Experiment Information
Experimental Design: Randomized complete block Number of Reps: 9 (3 blocks x 3 reps per block)
Materials & Methods: Plant Material and Culture. Seedling plugs of Abies fraseri and Pseudotsuga menziesii were received from Weyerhaeuser Company, Olympia WA on March 26, 2007. The plants were transplanted to 1-gallon pots containing UC Mix on April 5, 2007 and grown on in a greenhouse under natural day length and day/night temperatures of 75°/65° F. The experiment ran from April 20, 2007 to June 14, 2007 in an outdoor nursery under 50% shade (Table 4). The plants were irrigated daily during the 8-week experiment using an automatic drip system delivering 2L per hour. Applications of pesticides as part of a normal pest management program were made as needed (see above). Experimental Procedure. Thirty-six plants were randomly chosen and individually tagged for treatment with 0 (Control), 0.047 lb ai/acre (1X), 0.094 lb ai/acre (2X) or 0.188 lb ai/acre (4X) Sedgehammer with 9 replicates per treatment. These dosages were prescribed in IR4 Ornamental Protocol 07-011 (Appendix A). The plants received the first spray application on April 20, 2007 and the second application 4 weeks later on May 15, 2007.
IR-4 Ornamental Horticulture Program Trial Report
Researcher(s): Heiner Lieth, UC Davis PRNumber(s): 26165, 26166 10
Data Collection. Phytotoxicity ratings were taken at week 0, 1, 2, 4, 5, 6 and 8 (April 20, 26; May 3, 16; 24 and June 14, 2007). Visual phytotoxicity evaluations were based on a numerical rating scale ranging from 0 (no injury) to 10 (complete kill) (Table 3). Table 3. Numerical plant damage rating scale used for phytotoxicity determinations.
Rating Description of plant damage 0 No damage 1 No visible damage but unintended (non-permanent) impact 2 Slight leaf/tissue damage (curling leaves, necrosis, etc.) 3 Marginal chlorosis on some leaves (damage on up to 10% of plant) 4 10% – 20% of plant damaged 5 Significant damage to much of plant (30% - 40%) 6 40% – 60% of plant damaged 7 Chlorosis or necrosis on most of plant (60% - 70%) 8 Abscised leaves, branch dieback 9 Tissue severely damaged (80% - 100% of plant) 10 Complete kill
Plant height and width were measured at week 0 (April 20, 2007) and week 8 (June 14, 2007). Plant height (cm) was measured from the container soil surface to the top of the canopy. Plant width (cm) was measured twice along perpendicular lines at the widest part of the plant, resulting in W1 and W2. For each observation a canopy volume index was calculated so as to be able to determine if canopy volume was affected by the application of herbicide. The calculation was made as H*W1*W2, where H is the height and W1 and W2 are two width measurements. The usefulness of this index is based on the fact that many of the models for such a volume calculation are of the form a*H*W1*W2. The constant “a” depends on the assumption of the shape of the canopy. Since analyses of variance are scale-independent, the conclusion will thus be for the volume of the plant canopy. Statistical Analysis. The data were analyzed using Proc GLM of the Statistical Analysis System (SAS). The phytotoxicity and change in mean value from the starting plant height, width and volume index were analyzed for significant differences using t-tests. Acknowledgements: The research was supported through funding from the USDA IR-4 Program, Western Region based at UC Davis, Davis, CA. Personnel involved in this project included: Ron Lane (pesticide application, pest management) and Priyasheila Singh (plant culture, data collection). The materials being tested were supplied by the manufacturer/distributor. The plants were donated by Weyerhaeuser Company, Olympia WA.
IR-4 Ornamental Horticulture Program Trial Report
Researcher(s): Heiner Lieth, UC Davis PRNumber(s): 26165, 26166 11
Environmental conditions during the experiment: Table 4. Environmental conditions during the 8 weeks of the experiment to determine phytotoxicity of Sedgehammer on Abies fraseri and Pseudotsuga menziesii.
Researcher(s): Heiner Lieth, UC Davis PRNumber(s): 26165, 26166 12
Raw Data: Table 5. Phytotoxicity and plant growth data collected for plants of Abies fraseri treated with two applications of 0 (Control), 0.047 (1X), 0.094 (2X) or 0.188 (4X) lb ai/acre Sedgehammer at weeks 0 and 4 of a 8-week experiment. Phytotoxicity Report Form Abies Sedgehammer Trial Phytotoxicity at week Plant Size at week 0 Plant Size at week 8 Height Width1 Width 2 Height Width1 Width 2 Treatment Block Rep 0 1 2 4 5 6 8 (cm) (cm) (cm) (cm) (cm) (cm)
Control A 1 0 0 0 0 0 0 0 23.5 6 6 29 17 12 Control A 2 0 0 0 0 0 0 0 21 6 6 27 15 14.5 Control A 3 0 0 0 0 0 0 0 25 7.5 5 31 16.5 12.5 Control B 1 0 0 0 0 0 0 0 16 7 5 23 14.5 9 Control B 2 0 0 0 0 0 0 0 35 9 8 40 18 15 Control B 3 0 0 0 0 0 0 0 27 6 4 32 13 12 Control C 1 0 0 0 0 0 0 0 25.5 8 5 32 17 14.5 Control C 2 0 0 0 0 0 0 0 30 6 6 34 14.5 10 Control C 3 0 0 0 0 0 0 0 17 8 6 21.5 13.5 11
Researcher(s): Heiner Lieth, UC Davis PRNumber(s): 26165, 26166 13
Table 6. Phytotoxicity and plant growth data collected for plants of Pseudotsuga menziesii treated with two applications of 0 (Control), 0.047 (1X), 0.094 (2X) or 0.188 (4X) lb ai/acre Sedgehammer at weeks 0 and 4 of a 8-week experiment. Phytotoxicity Report Form Pseudotsuga Sedgehammer IR4 Trial Phytotoxicity at week Plant Size at week 0 Plant Size at week 8 Height Width1 Width 2 Height Width1 Width 2
Treatment Block Rep 0 1 2 4 5 6 8 (cm) (cm) (cm) (cm) (cm) (cm) Control A 1 0 0 0 0 0 1 0 48 14 13 61 27.5 22 Control A 2 0 0 0 0 0 1 0 49 18 18 62 32.5 30 Control A 3 0 0 2 2 2 0 2 37 13 10 45.5 20 18 Control B 1 0 0 0 0 0 0 0 42 13 11 58 32 28 Control B 2 0 0 0 0 1 2 1 37 16 15 44.5 18 17 Control B 3 0 0 1 1 2 3 1 42 13 12 52.5 21 17 Control C 1 0 0 0 0 1 1 0 52 16 15 64.5 31 27 Control C 2 0 0 0 0 0 1 0 40 18 18 60.5 41 37 Control C 3 0 0 0 0 1 2 0 42 14 17 52.5 30 27
Researcher(s): Heiner Lieth, UC Davis PRNumber(s): 26165, 26166 14
APPENDIX A Phytotoxicity to ornamental horticulture plants from tools to manage broadleaf weeds and sedges. Ornamental Protocol Number: 07-011 Objective: Determine phytotoxicity of Sedgehammer (Halosulfuron), Sulfentrazone 0.2G, and V-10142 to unlabelled perennial plants commonly grown in nurseries. Experimental Design:
Plot Size: Must be adequate to reflect actual use conditions. Replicates: Minimum of 3 replications (preferably 4) with 3 plants per replicate Application Instructions: Apply first application over the top of plants just breaking dormancy or, under climates
where plants do not go totally dormant, apply prior to active growth in the spring. For V-10142 75WG, apply directed spray instead of over the top. See table for product specific information.
Plant Materials: Contact your Regional Coordinator for an up-to-date list. Plants grown in field containers are preferred to in-ground.
Evaluations: Record plant height & width at initial and final evaluations. At 1, 2, and 4 weeks after each application, record phytotoxicity on a scale of 0 to 10 (0 = No phytotoxicity; 10 = Complete kill). If appropriate, also include ratings for chlorosis, defoliation, stunting or other growth effects on a scale of 0 to 10 (0 = No effect; 10 = Complete plant affected). If any phytotoxicity is observed in treated plants, take pictures comparing treated and untreated plant material.
If different application methods or evaluations are made, please clearly specify differences in final report and explain how they enhanced results.
Recordkeeping: Keep detailed records of weather conditions including temperature and precipitation, soil-type or soil-less media, application equipment, irrigation, liner size, plant height & width, and plant growth stage at application and data collection dates.
Treatments: Product Rate Special Instructions Contact Information
to obtain materials and any needed adjuvants
Sedgehammer 75WG (Halosulfuron)
1 oz per acre (0.047 lb ai) 2 oz per acre (0.094 lb ai) 4 oz per acre (0.188 lb ai)
Always use 0.25% v/v of a non ionic surfactant. If severe phyto symptoms do not occur and where feasible apply a second application 4-6 weeks later at identical rates.
V-10142 75WG + surfactant 1 lb per acre (0.75 lb ai/acre) 2 lb per acre (1.5 lb ai/acre) 4 lb per acre (2.0 lb ai/acre)
Only evaluate as directed spray on large shrubs or trees. Do not contact foliage with sprays. 2 directed applications on a 4 week interval Apply 0.5” of irrigation immediately after application
Untreated Reports: Reports submitted on the standard IR-4 Ornamental Horticulture Research Report Form are preferred. A report submitted electronically is preferred but not required. If the report is provided electronically, the basic report can be sent in MS Word or WordPerfect, the recordkeeping information as PDF or other electronic documents, and the raw data in MS Excel or other suitable program such as ARM. Please direct questions to: Cristi Palmer, IR-4 HQ, Rutgers University, 500 College Road East, Suite 201W, Princeton, NJ 08540, Phone 732-932-9575 x4629, [email protected]. Draft Date: 3/8/07 Revised By: CLP
