Fig. 2. Cumulative yield of all herbage in plots sown to old world bluestem (OWB) and perennial ryegrass (PRG) as a function of regrowth interval (RI) during the 2000, 2001, and 2002 growing seasons. Analysis of variance includes RI, species (S), harvest date (H), and the interactions. Each point is the mean of three replicates.