PARENT SESSION
Poster Session #54: Plant Ecology: Communities.
Thursday, August 8. Presentation from 8:00 AM to 9:30 AM. Exhibit Hall B & C, TCC

Limiting traits in early old field succession on a rich soil.

Gleeson, Scott^*,1, Yeargan, Bret¹, ¹ University of Kentucky, Lexington, KY

ABSTRACT- Plant succession was followed for 6 years on a plowed abandoned farm field in the rich limestone derived soil of the Inner Bluegrass Region of Kentucky. A replicated water and nutrient (N, P, K, and background nutrients separately and combined) enrichment experiment was maintained during the succession in 2mx2m plots. Each year an additional sector of the field was plowed in late spring to initiate succession. Species dominance changed dramatically in the first few years and was highly repeatable when initiated in subsequent years. Unlike resource experiments in other old fields, the enrichments had only minor impact on total biomass (which declined over time) or species composition. In the different aged fields in the fifth year, experiments tested various hypotheses about successional controls (germination, colonization, competition) on the dominant species. Idiosyncrasies of the species' life history traits appeared to be the primary controller, that is the succession was mainly driven by colonization (and extinction) rather than competition.

KEY WORDS: old field succession, fertilization, colonization, plant competition