Strategic planning of grass forage production in North-West Russia
Federal Scientific Agroengineering Center VIM, branch in Saint Petersburg, Filtrovskoje Shosse 3, p.o. Tiarlevo, RU196625 Saint Petersburg, Russia
*Correspondence: papushinea@yandex.ru
Abstract:
Energy and nutritional value of harvested forage rely heavily on grass vegetative phase and harvesting time. The study aimed to identify rational forage harvesting options in terms of harvesting time. The data for modelling were taken from the literature based on the results of many years’ research. The mathematical models of variation of grass mass and quality depending on days after emergence were created. The possible options of two-step harvesting of forage grass (cocksfoot, Dactylis glomerata) were considered using mathematical methods of nonlinear programming: (1) obtaining maximum hay mass with maximum feed units from specified area of 400 ha and maximum forage yield at full flowering of 15.0 t ha-1; and (2) identifying the harvesting timing and area to obtain the required amount of hay (2,500 t) with a target nutrient content (1,200 feed units). Problem 1 solution was harvesting 1 scheduled for the 45th day after emergence at full earing on 170 ha; harvesting 2 scheduled for the 69th day after emergence at full flowering on 230 ha. In this case, 2,066.5 t of hay with 947 feed units would be obtained. Problem 2 solution was harvesting 1 scheduled for the 43th day after emergence at middle earing on 250 ha; harvesting 2 scheduled for the 65th day after emergence at early flowering on 156 ha. The created models can be effectively applied for forage harvesting in any grassland area required and in any regions.
Key words:
cereal grass, forage harvesting, forage quality, modelling., non-linear programming, strategy, yes-no decision