Effect of autumn harvest date on herbage yield and composition of grasses and white clover

Abstract

In the maritime climate of Atlantic Canada, herbage growth declines rapidly during the cool and wet autumn period. This shortens the effective growing season by 6 to 10 weeks and impacts on herbage supply. The objectives of this study was to determine yield, tiller population, ground cover and herbage composition of five cool-season grasses and white clover ( Trifolium repens) in the third cut, 36, 56 and 76 days after the second harvest on 5 August. The dry-matter accumulation in the autumn was greatest for orchardgrass ( Dactylis glomerata) and tall fescue ( Festuca arundinacea). Orchard-grass yield increased to 10 September while that of other grasses and white clover increased to 1 October. Reed canarygrass ( Phalaris arundinacea) was the most persistent species. White clover had high in-vitro digestibility of dry matter (IVDDM), nitrogen and low neutral and acid detergent fiber contents. The in-vitro digestible dry matter of orchardgrass declined more rapidly than that of other species in the autumn. The S, Zn and Cu concentrations were below critical levels for plant and animal health.