Living Eucalyptus obliqua trees and logs as habitat for wood-inhabiting

fungi in southern Tasmania

Anna HopkinsCRC-Forestry & University of Tasmania

Current address: Scion Forest Biosecurity and Protection, Rotorua, New Zealand

Forestry in TasmaniaForestry in Tasmania

Rotation lengths of 80-100 years

Reduction of old growth trees (>150 yrs)

Reduction of large diameter logs (>120cm)

Alteration to stand and CWD dynamics

Forests still largely untouched, unharvested

Research Questions:Research Questions:

•What fungi are found within living Eucalyptus obliqua trees and logs?

•Is there a change in the number and community structure of wood-inhabiting fungi:-as trees age?-in large and small diameter logs?-in regrowth and mature forests?

•Eucalyptus obliqua in native forests in Southern Tasmania

•At the Warra LTER and surroundshttp://www.warra.com/

•60 km south-west of Hobart

MethodsMethods

Cultures of wood-inhabiting fungi

Traced patterns of decay

Incubated decayed wood on specialised media

Dissected stem/log at several points

MethodsMethods

•Two studies on E. obliqua:

•18 trees (69yo, 105yo, >150yo)

•36 logs - large (>85 cm) & small (30-60 cm)- logging regeneration & mature forest

•Associated with beetle and rot type studies

Morphospecies of beetlesRotten wood types

• Trees:• Over 300 individual fungal isolates• 91 species: 20 common, 71 only found once• 57 species unnamed to order• Common taxa: Postia, Coniophora, Hymenochaetaceae,

Athelia, Stereum.

• Logs:• More than 500 fungal isolates• 60 common species: 28 named• Common taxa: Postia, Coniophora, Ganodermataceae,

Armillaria

Mature trees have more species

Significantly more species in old trees (>150yo)

Younger age classes had similar numbers of species

Totals: >150 = 56, 105 = 21, 69 = 26

024

68

1012

1416

69 105 >150

Tree Age Class

Num

ber o

f Spe

cies

of F

ungi

Small trees are still significant

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Cumulative cross-sectional area (cm2)

Num

ber o

f Spe

cies

69105>150

Adjusting for sampling effort:

More species in 69yo trees when equal samples compared

Mature trees have different fungi

Mature trees (>150yo) have distinct communities of wood decay fungi

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69

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>150

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Cumulative Cross-Sectional Area (cm2)

Estim

ated

Num

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Small

Large

Fungi change with log size

•More species in small logs when equal samples compared

Fungi change with log size and forest type

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Canonical axis for forest type

Can

onic

al a

xis

for l

og s

ize

Regenerating forest, Large log

Regenerating forest, Small log

Mature forest, Large log

Mature forest, Small log

•Fungal community composition is affected by:-Log size-Forest type•Large logs & mature trees similar

Are old trees and large logs special?

-Inventory of fungi-Mature trees (>150yo) & large logs important for fungal biodiversity-Younger trees and small logs also important for fungal biodiversity-Fungal community changes with forest type

-Patterns supported by beetle and rot data

Implications for forest managementImportant to retain structural complexity throughout the forest landscape

-Mature trees and large logs important for fungal diversity-Fungi with specific preferences for habitat-Fungi may have a specific functional role

Current trial of aggregated retention (15-30% retained)-Retention of living trees within stands-Temporal continuity of tree ages

Advocate adaptive management techniques-Dispersal capabilities of fungi-Effect of microclimate and edge effects

AcknowledgementsAcknowledgements

Jack Simpson (State Forests, NSW)

David Ratkowsky (UTas)

Genevieve Gates (UTas)

Marie Yee (Forestry Tas)

Kate Harrison (CRC-F/UTas)

Yuan Zi-Qing (UTas)

Simon Grove (Forestry Tas)

Tim Wardlaw (Forestry Tas)

Caroline Mohammed (CSIRO/UTas)

Morag Glen (CSIRO)

Malcolm Hall (CSIRO)

Holsworth Wildlife Research Grant

Warra Grant fromForestry Tasmania