Potential patch dynamics on a roadside embankment: interactions between crownvetch and Kentucky-31 tall fescue.
Contiguous patches of vegetation, dominated by either crownvetch or Kentucky-31 tall fescue (Festuca arundinacea Schreb.), were studied on a revegetated roadside embankment in Kentucky. The purpose of the study was to predict future patch dynamics. Nitrogen fertilization (25 g m-2) in the field significantly increased shoot growth of fescue, while phosphorus fertilization (25 g m-2) in the field significantly increased shoot and fine root growth of crownvetch. In alien soils (greenhouse experiment) or in alien patches (field), fescue growth was enhanced or was unaffected as compared to growth in home soils or home patches. The growth of crownvetch in alien soils or alien patches was consistently inhibited as compared to growth in home soils or home patches. Greenhouse experiments with mixed cultures and monocultures showed fescue to be the superior competitor at a 1:1 density relationship. It is predicted that fescue will eventually dominate this land surface in the absence of further management.