A cost-benefit study of alternative policies in making grass silage

Abstract

An improved operational research model for forage conservation systems has been devised which simulates the conservation process in relation to the weather and a cost-benefit study has been carried out of a number of alternative mechanization policies for making grass silage. These alternatives include wilting to various degrees or direct cutting, wilting in spread swaths with periodic tedding or leaving the mower windrow undisturbed, chopping to various degrees using a precision chop harvester with different set chop lengths, a double chop harvester, a flail harvester, or a big baler, and the use of additives. Each option has been costed. Benefits have been assessed in terms of the value of the reduction in requirement for concentrate supplementation in a ruminant diet with increased silage quality. The study makes a good economic case for wilting silage and for harvesting using a precision chop harvester or, for a small farm, a big baler, but not for the use of formic acid based additives or for spreading or tedding treatments to swaths.