Wintering cows in Southland using a hay bale grazing approach: some benefits for animals and the environment

Improved approaches to animal wintering are an important and an on-going focus of research effort in the southern South Island. The task of developing wintering options that simultaneously improve animal welfare and environmental outcomes, are farmer-friendly, and ensure that businesses remain financially viable, is a complex challenge that requires an integrated assessment across a range of domains and performance indicators. A hay bale grazing method (hereafter referred to as “bale grazing”) has been identified as anoption that could potentially deliver these integrated benefits. This practice originated in the US as part of the development and application of some regenerative farming principles, particularly the concept of maintaining “soil armour” by ensuring plant cover and root thatch is retained within a grazed system. This principle is particularly relevant to intensive winter grazing activities, where crop-based wintering methods typically result in the removal of most protective soil armour when paddocks are grazed. In contrast, in NZ, a bale grazing wintering approach seeks to maintain a viable pasture that can re-grow as temperatures begin to warm in spring. Hay is provided to act both as a source of dietary feed and as a location where animals can more comfortably lie on any un-eaten hay residues. An important design feature of the bale grazing method is that grazing intensity is approximately half that observed for more traditional forage crop wintering approaches, helping to alleviate soil treading damage, resulting in less mud, and a relatively rapid recovery of plant growth and nitrogen (N) uptake in spring. This latter effect will likely help to reduce the risk of N losses in drainage.