Effects of Beech Bark Disease and Silvicultural Management in Northern

Hardwood Ecosystems: Tree Growth, Tree Regeneration, and Invertebrate Biodiversity

John Witter

Jennifer Stoyenoff

Erin Thompson

Holly Petrillo

Julie Yocum

Beech Bark Disease Monitoring in Michigan

Causal Agents:•Beech scale

•2 species Nectria Exotic pest

• Objective: Temporally and spatially monitor the impact of beech bark disease (BBD) on beech trees and northern hardwood ecosystems

• Cooperative Project between U of M, MDNR, USDA Forest Service, MSU and MTU

• Monitoring plot system– Intensive (40) and Extensive (140)– Measuring numerous variables that together create a

picture of the health of the forest

McIntire-Stennis Project 2002-2004

• The monitoring study will continue during the next three years and that study is completely funded by MDNR

• However, MDNR funds cover the monitoring aspect (temporal and spatial change) of BBD in MI forests. It does not cover any funding for research.

• With this McIntire-Stennis project we are going to address 3 research areas: tree growth, tree regeneration, and invertebrate biodiversity

Research Questions

• What effects do the presence of BBD and silvicultural treatments in northern hardwood stands have on the growth of existing American beech trees?

• What effects do the presence of BBD and silvicultural treatments in northern hardwood stands have on tree regeneration?

• What effects do the presence of BBD and silvicultural treatments have on biodiversity of key invertebrate groups present in northern hardwood ecosystems?

Treatment Types: Three Factors Involved

• Geographic location (2)– Lower Peninsula, Upper Peninsula

• Presence of exotic scale (2)– No scale and heavy scale

• Silvicultural treatment (3)– No silvicultural treatment

– Recent selection cut (past 2 years)

– Old selection cut (past 10-14 years)

• 2 x 2 x 3 x 5 (replicates/treatment) = 60 stands

Growth of American beech

Tree Regeneration

• Size distribution and origin (seed or sprout)

• Looking at seedlings by height class

• Overall beech seedling density for each plot

Biodiversity and Invertebrate Groups

• Pitfall traps• Collected organisms will be counted and grouped

by major taxa• 2 groups (ground beetles and isopods) will be

identified to the species level• In future years we will form partnerships to bring

on additional cooperators that will work with groups such as springtails, ants, spiders and centipedes

Expected Outcomes

• How will BBD and management actions affect key processes in the northern hardwood forest (tree growth and regeneration)

• How will BBD and management actions affect the biodiversity of various invertebrate groups in northern hardwood forests

• It will increase our knowledge of ground beetles and isopods and will give us new knowledge on using these groups as indicators of ecosystem functioning and change in temperate hardwood forests