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Secondary invasion following the reduction of Coronilla varia (Crownvetch) in sand prairie

Amy J. Symstad
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Abstract

I investigated the effect of Coronilla varia invasion and subsequent reduction on the plant community and soil nitrogen availability in a degraded Illinois sand prairie. The presence of C. varia significantly increased soil nitrogen availability and significantly decreased native species richness and cover, but neither helped nor hindered a common non-native grass, Poa pratensis . One year after the drastic reduction of C. varia , soil nitrogen remained somewhat elevated and native species richness and cover low, but P. pratensis cover increased nearly six-fold. These results suggest that C. varia 's impact might be continued through altered soil nitrogen. More important, however, was the strong response of P. pratensis , which could hinder restoration efforts by competing with native species.

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Amy J. Symstad. 2004. Secondary invasion following the reduction of Coronilla varia (Crownvetch) in sand prairie. https://doi.org/10.1674/0003-0031(2004)152%5B0183%3Asiftro%5D2.0.co%3B2

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