Buchtel College of Arts and Sciences

Date of Last Revision

2021-12-16 06:51:56



Honors Course

3100 499 - Senior Honors Program in Biology

Number of Credits


Degree Name

Bachelor of Science

Date of Expected Graduation

Spring 2022


Ohio forests are threatened by the invasive ecosystem engineer A. agrestis. A. agrestis invasion typically co-occurs with the ecosystem engineer, Odocoileus virginianus, where their impacts may synergize. To determine the direct effects of A. agrestis invasion, fenced plots across the Cuyahoga Valley National Park that excluded deer were utilized. The species richness, Shannon diversity and evenness of woody understory flora was measured in each plot. Mustard extraction was used to determine earthworm abundance. Correlations between abundance and measured variables were used to highlight potential invasion effects. Abundance and species richness was found to have a significant, positive correlation (p = 0.042, r = 0.67). Abundance and diversity, and abundance and evenness, were not significantly correlated (p = 0.16, r = 0.5, and p = 0.22, r = -0.48 respectively). Invasion by A. agrestis may facilitate an increase in species richness in the woody understory, while potentially having no significant impact on diversity and species evenness. These results contradict previous studies. However, these results match a previous study in the CVNP that also utilized fenced plots. This suggests that the direct effects of A. agrestis on woody understory flora may be different than those observed in the presence of White-tailed Deer.

Research Sponsor

Dr. Randall Mitchell

First Reader

Dr. Christine Sprunger

Second Reader

Tvisha Martin

Honors Faculty Advisor

Brian P. Bagatto



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