Field and microplot data collected over three seasons were used to determine relationships between initial (Pi) and final (Pf) population densities of Meloidogyne spp. and Paratrichodorus minor on winter cover crops of rye (Secale cereale) in north Florida. Log-transformed Pf and Pi were linearly related for Meloidogyne arenaria race 1 and M. incognita race 1. For data pooled across locations and seasons from sites at which M. arenaria predominated, the relationship between Pf and Pi was expressed by the equation log e (Pf+1) = 0.863 log e (Pi+1) - 0.26 (r=0.863; P 0.01). This equation indicates that existing population densities of M. arenaria will be nearly maintained by a winter cover crop of rye, but without increasing above Pi levels. Pf of P. minor was linearly related to Pi for each site and season, but there was no consistent relationship across sites and seasons.