| Maize (Zea mays L.) hybrids developed for short season environments (2000-2200 Corn Heat Units [CHU]) may be capable of achieving silage maturity in central Alberta. In one experiment at seven locations, increasing plant density from ∼50 000 to ∼124 000 plants/ha -1 delayed silk emergence 5 days, reduced starch content 4%, reduced silage dry matter percentage at harvest from 31% to 35%, and resulted in a linear increase in dry matter yield (P < 0.05). Another experiment lowering the row spacing from 76 to 38cm (at ∼74 000 plants ha-1) did not alter (P > 0.05) any agronomic or quality trait except predicted milk yield (tha-1). Narrow row spacings may increase (P < 0.01) milk per ha. Lower (2000) CHU hybrids exhibited greater adaptation than those rated >2000 CHU. They yielded more predicted milk per ha with acceptable (>30%) dry matter for ensiling as plant density increased, at any row spacing. |
