EFFECTS OF PLANT POPULATION ON FORAGE CORN YIELDS AND MATURITY ON PRINCE EDWARD ISLAND

Abstract

Plant population effects on yield and maturity were measured on forage corn over 4 yr at Charlottetown, P.E.I. Populations ranged from 39,000 to 80,000 plants/ha and had relatively little effect on forage yields. Yields varied from 4,887 kg/ha to 15,289 kg/ha, but the variation was mostly related to seasonal effects. Whole plant percentage dry matter contents, though in the low 20’s, were typical for the area and were essentially unaffected by population. The percentage dry matter in the grain tended to decrease at the higher population, but only significantly so in 2 yr (P = 0.1). High population retarded silking dates. In the 3 yr that tissue nutrient concentrations were measured, increasing population had little effect on total nutrient uptake but significantly reduced whole plant nutrient concentrations in 1 yr (P = 0.05). Under the climatic conditions of the Atlantic area, field stands of 50,000–80,000 plants/ha appear suitable for forage corn.