1. Analysis of Temporal and Spatial Changes in Michigan’s Forests John A. Witter Julie L. Yocum Jessica Jeffries Yuri Sasaki Jennifer Stoyenoff

2. Objectives Examine the effects of disturbance types and levels on forest conditions (Example: basswood decline) Analyze the effects of thinning treatments on forest productivity in Michigan oak stands Provide data to user groups and attain additional funding

3. Effects of Disturbance Types and Levels on Basswood in Northern Hardwood Forests (Basswood Decline) Characteristics of basswood Importance of basswood History and stressors of basswood decline Study areas and results Summary

4. Characteristics of American Basswood Shade Tolerant Moderately slow growing, Long-lived Reproduction: Stump sprouts and seeds

5. Common in MI, WI, MN Found in many different ecosystems such as: - Rich, moist northern hardwood forests to drier, more nutrient depleted sites - Lakes, stream borders and bottomlands

6. Importance of Basswood Recreation Aesthetics Habitat and food source for wildlife Timber- plywood, carving materials, veneer, and many other products

7. In 1985, in WI alone, introduced thrips caused moderate to severe defoliation on basswood in ca. 250,000 ha Monitoring systems in the Great Lakes region have reported increases in basswood mortality, crown dieback, and defoliation This led to mangers, and forest health specialists becoming concerned about possible decline in basswood These results led to a basswood decline evaluation study for the Great Lakes region 1998-2002 Indication of Basswood Decline

8. Stressors Drought Insects –Introduced basswood thrips –gypsy moth – forest tent caterpillar Wind Competition

9. Study Areas Michigan data (MIMS) 1992-2001 Great Lakes Evaluation 1998-2001 –Intensive plots 1998-2001 –Extensive plots 1999

10. Basswood Plot Locations in the Great Lakes States

11. Cumulative Basswood Mortality in Lower MI

12. Live Basswood BA 1992-2001

13. Dead BW Basal Area by Soil Type

14. Live BW Basal Area By Soil Type

15. Basswood Mortality By Crown Class

17. Summary: Is Basswood Decline Real? Percent cumulative dead stems have increased 4-fold during the last 10 years. Decline is real based on cumulative stem mortality. Overall live basal area has decreased between 1995 and 2001. Decline is real based on live basal area.

18. It remains to be seen whether mortality in the codominant crown class will continue to increase during the next few years. If it does continue to increase then the decline is real. If this mortality/decline is natural thinning that occurs when basswood stems reach about 75 years of age, then what we may be calling decline is only a natural successional process. Summary Cont’d