Biodiversity across the forest cycle in ash and Sitka spruce plantations: Stand structure and vegetation change Laura French, George Smith, Saoirse O’Donoghue, Anne-Marie McKee, Sue Iremonger, Daniel Kelly, Fraser Mitchell Department of Botany, Trinity College Dublin

University College, Cork University of Dublin, Trinity College Coillte Teoranta

Forestry and biodiversity Forestry an increasing land use in Ireland

Forestry and biodiversity Forestry an increasing land use in Ireland Can represent a threat to existing biodiversity

Forestry and biodiversity Forestry an increasing land use in Ireland Can represent a threat to existing biodiversity Can be an opportunity to enhance biodiversity at local and landscape scales

Forestry and biodiversity What is the biodiversity of commercial forestry plantations?

OR?

Objectives How does stand structure develop in plantations?

Objectives How does stand structure develop in plantations? How does species richness change over the forest cycle?

Objectives How does stand structure develop in plantations? How does species richness change over the forest cycle? How does tree species influence vegetation species richness?

Objectives How does stand structure develop in plantations? How does species richness change over the forest cycle? How does tree species influence vegetation species richness? How does species richness of typical woodland plants change?

Study sites 20 Sitka spruce 12 ash 12 spruce-ash mix Spruce yr old Ash yr old 3 100m 2 plots per site / species combination Sitka spruce ash

Sitka spruce structural types PCA Ordination Axis 1 (Var Expl = 73%) Axis 2 (Var Expl = 21%) Prethicket 30% Canopy Cover

Prethicket spruce site: Brackloon, Co. Galway

Sitka spruce structural types PCA Ordination Axis 1 (Var Expl = 73%) Axis 2 (Var Expl = 21%) Thicket 80% Canopy Cover

Sitka spruce structural types PCA Ordination Axis 1 (Var Expl = 73%) Axis 2 (Var Expl = 21%) Closed-maturing 87% Canopy Cover

Closed-maturing spruce site: Buffanoky, Co. Limerick

Sitka spruce structural types PCA Ordination Axis 1 (Var Expl = 73%) Axis 2 (Var Expl = 21%) Reopening 71% Canopy Cover

Sitka spruce structural types PCA Ordination Axis 1 (Var Expl = 73%) Axis 2 (Var Expl = 21%) Mature 55% Canopy Cover

Mature spruce site: Union Wood, Co. Sligo

Species richness over the Sitka spruce forest cycle Mean species richness per plot Vascular plantsBryophytes A B C BC A A C B

Canopy cover and species richness y = x R 2 = Canopy cover (% cover per 100 m 2 quadrat) Mean total species richness per plot

Ash canopy cover

Pole ash site: Coolross, Co. Tipperary

Ash canopy cover

Closed-maturing ash site: Sinnot’s Bog, Co. Wexford

Ash canopy cover

Species richness over the ash forest cycle Mean species richness per plot Vascular plantsBryophytes AA BBB A AB B B

Ash compared with Sitka spruce Mean species richness per plot AshSitka spruce A B A AA B

Woodland species over the forest cycle Mean species richness per plot AshSitka spruce A AB C B A A CD D BC

Conclusions Species richness changes significantly over the forest cycle

Conclusions Species richness changes significantly over the forest cycle Ash forests have higher species richness of vascular plants

Conclusions Species richness changes significantly over the forest cycle Ash forests have higher species richness of vascular plants Sitka spruce forests have higher species richness of bryophytes

Conclusions Species richness changes significantly over the forest cycle Ash forests have higher species richness of vascular plants Sitka spruce forests have higher species richness of bryophytes Species richness of woodland vascular plants increases along forest cycle

Conclusions Plantations of ash and Sitka spruce are not necessarily “ecological deserts”

Conclusions Plantations of ash and Sitka spruce are not necessarily “ecological deserts” Not “oases of biodiversity” either

The BIOFOREST project is funded by the National Development Plan through the EPA and COFORD as part of the Environmental RTDI Programme Project Website: