EXTENDING THE GRAZING SEASON

Resumen

It is accepted that grazed grass of high quality is the cheapest feed resource for ruminant animal production. Thus, maximizing its use aids the economic viability of grassland farming systems, this objective being increasingly necessary in light of the highly competitive marketplace. This review deals with the forage production and utilization strategies which have been developed, some of which were developed in the past and others of more recent vintage. Choosing suitable plant species for the specific growing conditions which pertain is a key element and such species can range from annual forage crops to perennial grasses and legumes. The time of application of fertilizers, particularly nitrogen, is another strategy particularly important for the provisión of early or late season grazing. In semi-arid regions irrigation is an obvious option provided water is available and inexpensive. However, in such regions sight should not be lost of drought resistant plant species including shrubs and trees that can be grazed. Allowing grass to accumulate (the grass 'wedge' or 'bank', deferred grazing, stockpiling) can provide forage for utilization in dry summer periods or late season. In utilizing growing or saved grass efficiently, techniques can vary from limited short^ period grazing or rationing to full-time grazing, and in method from strip grazing to continuous stocking with the use of optimal sward surface heights as a guide to controlling intensity of use. Experimental work has proven the case for the various strategies of extending the grazing season and improving animal output in a range of environments. The challenge on individual farms is to achieve year-round integration of selected management practices suitable for the specific farm environment