Testing a rapid Floristic Quality Index on headwater wetlands in central Pennsylvania, USA

Floristic Quality Assessment is a proven technique for evaluating the condition of a variety of habitats including wetlands. Its utility in state monitoring and assessment programs, however, has been curtailed by the additional effort and expertise needed for deployment. In this study, we tested the validity of two prerequisites of floristic quality assessment: the need for a comprehensive species list and the requirement that all taxa be identified to species. The mean coefficient of conservatism (mean C) was shown to be the most sensitive variable of the index and was used to test its efficacy in a rapid context. Mean C demonstrated a lack of significant response when graminoid taxa were selectively removed and also when scores were calculated based on dominant taxa only (C¯_dom). The muted response observed is likely due to redundancy in the species list (many plants with the same C value) and the averaging of C values. Site ranks did shift when based on C¯_dom, however, and this result may have implications on how individual sites are prioritized for restoration and protection. Ultimately, resource managers must determine if the decreased level of accuracy obtained from abridged plant lists is an acceptable trade-off for increased savings in time and effort.