PARENT SESSION
Monday, August 7, 5:00-6:30 pm
Poster Session 2 - Invasive species
Exhibit Hall, Ballroom Level, Cook Convention Center

Potential allelopathic effects of the invasive Lonicera maackii (Amur honeysuckle) on native herbs.

Castellano, Steven¹, Boyce, Richard^*,1, ¹ Northern Kentucky University, Highland Heights, KY

ABSTRACT- We investigated effects on growth and germination of native plants resulting from potential chemical release from Lonicera maackii. Seedlings of Echinacea purpurea, Rudbeckia hirta, Monarda fistulosa, and Symphyotrichum novae-angliae were grown in soil amended with L. maackii litter, watered with extracts of L. maackii foliage, or grown under a surface layer of dried L. maackii foliage. Seedling survival was analyzed with survival analysis using the statistical program R. Leaf areas and stem heights were measured for each plant, fit to a logistic curve, and analyzed with ANOVA. Seeds of E. purpurea, Ratibida pinnata, Panicum virgatum, and Sorghastrum nutans were germinated in amended soil and compared to controls using survival analysis. Results show R. hirta had low survival and E. purpurea had reduced growth in amended soils. Extract treatments resulted in less growth for E. purpurea, but this was not significant. S. novae-angliae and M. fistulosa were unaffected by treatments. Seed germination of E. purpurea and R. pinnata was significantly reduced in amended soil, but P. virgatum and S. nutans germination was not. Surface treatments increased mortality of E. purpurea and R. pinnata, but had little effect on growth. Results indicate the potential for L. maackii to chemically alter plant community structure.

Key words: invasion ecology, allelopathy, Lonicera maackii