The epiphytes of Sitka spruce (Picea sitchensis) in Irish

plantation forests

Linda Coote, Daniel L. Kelly, Paul Dowding

BIOFOREST project, Department of Botany, Trinity College Dublin.

CONTEXT

Forest cover in Rep. of Ireland 10% Aim to increase to 17% by 2030 Plantations of exotic conifers – Sitka

spruce 50% of estate Little information on Irish plantation

forest biodiversity BIOFOREST project – 5 year Impact of afforestation and

forest operations on flora and fauna

Epiphytes Component part of BIOFOREST project Epiphytes of mature and over-mature

Sitka spruce and larch (Larix spp.) Main epiphyte groups -

lichens, mosses and liverworts

Important part of native woodland diversity

Little published information© Sylvia Sharnoff

AIMS

To assess the diversity of epiphytes in Irish Sitka spruce (Picea sitchensis) plantations

To examine the effects of open spaces within these forestry plantations on this diversity

SW Cluster

E Cluster

SITES

KNOCCLEA

REAN

MEENGLAN

CARR

CURA

MUCK

STOEBMUT

ATHN

LUGG

SITES

METHODOLOGY 12 mature Sitka spruce sites 1 open space per site

- 9 glades- 2 roads- 1 ride

N side (S-facing) of open space

1 tree at edge, 1 in forest interior – 24 total

L: 130cm

B: 25cm

M: 1/3 height of tree

U: 2/3 height of tree

25cm x 50cm plots on N & S aspect

20 plots per tree

Total: 478 plots

4 branches

RESULTS

1. Geographical clusters – SW vs. E of Ireland

2. Effect of open space - Edge vs. Interior trees

3. Aspect - N and S side of tree4. Vertical distribution – B to U trunk5. Horizontal distribution – inner to

outer branch

1. Geographical clusters

Species richness

Species richness

31 25 19

58

45

32

2

2

0

10

20

30

40

50

60

70

80

90

100

Total SW cluster E cluster

Sp

p.

rich

nes

s

Vascular

Lichens

Bryophytes

(91) (51)(72)

Species richness

Total 91 species

26 found in only 1 of 478 plots

35 found on only 1 of 24 trees

Only 17 species in more than

5% of plots

Species richness

Species richness

10.005.42

10.67

10.17

0

5

10

15

20

25

SW cluster E cluster

Ave

rag

e sp

p.

rich

nes

s

Lichens

Bryophytes

Significant difference in bryophyte spp. richness (p = 0.009) and total spp. richness (p = 0.002) between SW

and E

Percentage cover

Percentage cover

32.30

19.77

3.35

1.94

0

5

10

15

20

25

30

35

40

SW cluster E cluster

Ave

rag

e %

co

ver

Lichens

Bryophytes

Significant difference in average bryophyte cover (p = 0.033)

Nonmetric Multidimensional Scaling

(NMS) Ordination

2. Effect of open spaces

Species richness

Species richness

8.00 7.42

10.00 10.83

0

5

10

15

20

25

Edge Interior

Ave

rag

e sp

p.

rich

nes

s

Lichens

Bryophytes

No significant differences in species richness between edge and interior trees

Percentage Cover

No significant differences in average percentage cover between edge and interior

trees

Percentage cover

12.0310.14

1.39

1.41

0

2

4

6

8

10

12

14

16

Edge Interior

Ave

rag

e %

co

ver Lichens

Bryophytes

NMS Ordination

3. Aspect

Species richness

Species richness

5.79 5.88

7.08 7.92

0

2

4

6

8

10

12

14

16

N S

Ave

rag

e sp

p.

rich

nes

s

Lichens

Bryophytes

No significant differences in species richness between N & S side of trees

Percentage cover

Significant difference in average lichen cover (p = 0.005) and total cover (p = 0.023)

Percentage cover

10.1512.01

1.870.93

0

2

4

6

8

10

12

14

16

N S

Ave

rag

e %

co

ver

Lichens

Bryophytes

4. Vertical distribution

Factors which change with height - Decrease in humidity Increase in light levels Decrease in age/time for

colonisation

Bryophytes on trunk

Bryophyte cover in trunk plots

0

10

20

30

40

50

60

70

BN BS LN LS MN MS UN US

Ave

rag

e %

co

ver

Lichens on trunk

Lichen cover in trunk plots

0

2

4

6

8

10

12

14

16

BN BS LN LS MN MS UN US

Ave

rag

e %

co

ver

Bryophytes vs. lichens

Most bryophytes restricted to or mainly occurring on trunks Exceptions

Ulota crispaFrullania dilatataColura calyptrifolia

Bryophytes vs. lichens Most lichens found only or more

frequently on branches Trunk only- Graphis scripta,

Cladonia spp. More frequent on trunk-

Dimerella luteaLecanora pulicarisLepraria incanaParmelia sulcata

Kindbergia praelonga

Kindbergia praelonga

0

1

2

3

4

5

6

7

B L M U

Ave

rag

e %

co

ver

Hypnum jutlandicum

Hypnum jutlandicum

0

5

10

15

20

25

B L M U

Ave

rag

e %

co

ver

Metzgeria temperata

Metzgeria temperata

0

5

10

15

20

25

B L M U

Ave

rag

e %

co

ver

Ulota crispa

Ulota crispa

0

0.1

0.2

0.3

0.4

0.5

0.6

B L M U

Ave

rag

e %

co

ver

Hypotrachyna revoluta

Hypotrachyna revoluta

0

0.5

1

1.5

2

2.5

B L M U

Ave

rag

e %

co

ver

Dimerella lutea

0

1

2

3

4

5

B L M U

Ave

rag

e %

co

ver

Dimerella lutea

5. Horizontal Distribution

Factors which change with distance from trunk: Decrease in humidity Increase in light levels Decrease in age/time for

colonisation

Bryophytes on branches

Byophyte cover on branches

0

0.2

0.4

0.6

0.8

1

1.2

Inner Mid Outer

Plot

Ave

rag

e %

co

ver

Lichens on branches

Lichens cover on branches

0

0.2

0.4

0.6

0.8

1

Inner Mid Outer

Plot

Ave

rag

e %

co

ver

Hypnum jutlandicum

Hypnum jutlandicum

0

0.05

0.1

0.15

0.2

0.25

Inner Mid Outer

Plot

Ave

rag

e %

co

ver

Metzgeria temperata

Metzgeria temperata

0

0.1

0.2

0.3

0.4

0.5

0.6

Inner Mid Outer

Plot

Ave

rag

e %

co

ver

Ulota crispa

Ulota crispa

0

0.05

0.1

0.15

0.2

0.25

Inner Mid Outer

Plot

Ave

rag

e %

co

ver

Dimerella lutea

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

Inner Mid Outer

Plot

Ave

rag

e %

co

ver

Dimerella lutea

Fuscidea lightfootii

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

Inner Mid Outer

Plot

Ave

rag

e %

co

ver

Fuscidea lightfootii

SUMMARY Significantly greater total spp. richness,

bryophyte spp. richness & average bryophyte % cover in SW compared to E

Separation of SW and E sites in NMS suggests differences in spp. composition

No significant differences in spp. richness and % cover between Edge and Interior trees

Some separation of Edge and Interior trees in NMS suggests differences in spp. composition

SUMMARY 2 No significant difference in species

richness between N and S side of tree but significantly greater average lichen cover and total cover on S

Difference in vertical distribution of bryophytes and lichens with overall bryophyte cover decreasing with height and overall lichen cover increasing

Bryophytes more common on trunk and lichens more common on branches with some exceptions

SUMMARY 3 Differences in Vertical distribution of

individual species on trunk and Horizontal distribution on branches, probably related to microhabitat requirements

Acknowledgements Dr Daniel L. Kelly, Dr Paul Dowding,

Dr George F. Smith, BIOFOREST project, Department of Botany, Trinity College Dublin

COFORD (National Council for Forest Research & Development)

EPA (Environmental Protection Agency)