1. Geographic Variation in the Allelopathic Potential of American Beech (Fagus grandifolia) Emily A. Neidhardt Faculty Mentor: Dr. David B. Vandermast Elon University

2. The Nature of American Beech  Two races  Red & Gray Beech  Gray Beech  Grows clonally  Few genets, hundreds of ramets  Potential input of allelopathogens is high

3. Allelopathy  Chemical warfare between plants  A mechanism for changing forest diversity  Competitive advantage  A subset of secondary metabolites  Black walnut (Juglans nigra)  American beech is allelopathic, but less well known as such

4. American Beech & Allelopathy  Allelopathy is a factor in explaining “beech gaps” in Great Smoky Mountains National Park (Poteat and Vandermast 2010)  Stands of American beech become monodominant  Beech leachate shown to lower leaf area/biomass in sugar maple seedlings (Hane et al. 2003)

5. The Big Picture  Is allelopathy in American beech a species- wide trait or is it limited geographically to one race of American beech?

6. The Big Picture  If allelopathogen production is under heavy selective pressure…  No effects from red beech should be observed on spruce and fir because they do not interact within the studied area  If the trait is species-wide…  Inhibitory effects could occur on germination of spruce and fir

7. Experimental Design  Preparation  Leachate production L1 = 1200 g/15 L L2 = 600 g, 15 L  Collection of red beech forest soils  Cold stratification of red spruce and Fraser fir seeds

8. Experimental Design  Treatment groups  Commercial topsoil used as control for beech forest soil  Deionized H2O used as control for leachate  Red spruce, Fraser fir, and black simpson lettuce seeds  Germination data and aboveground biomass recorded

9. Results – Germination

10. Results – Above Ground Biomass