Volume 27, 162

Tropical Grasslands (1993) Volume 27, 162–179

Northern dairy feedbase 2001.
3. Winter pastures and crops

W.J. FULKERSON¹, K.J. LOWE², J.F. AYRES³ and T. LAUNDERS⁴

¹NSW Agriculture, Wollongbar,
²Queensland Department of Primary Industries, Ipswich Queensland, Australia
³Glen Innes and
⁴Taree, NSW

Abstract

Pastures based on temperate species are essential so that the subtropical dairy industry can maintain an even flow of milk to factories throughout the year, and are critical in balancing lower quality roughages and cereal grains.
Available soil moisture is the greatest limitation to growing temperate pasture species in the tropics and subtropics although other factors like excess heat, low pH and waterlogging also limit production.
With effective irrigation and the ample solar radiation, very high DM yields can be obtained (> 25 000 kg/ha DM) although persistence of perennial temperates is a problem.
Basic studies are being undertaken to understand the response of temperate species to the subtropical environment as a means of defining a more appropriate management system and acquiring more suitable plant material.
A broad program of breeding–selecting of grasses, forage crops and legumes is in place which should result in plant material more suited to the subtropics than the more temperate dairying areas. This needs to be ongoing. Appropriate selection criteria are still being defined but for perennials summer activity and resistance to heat are important and resistance to 'rust' is generally critical.
The emphasis has swung more towards clover–ryegrass from 'high N–ryegrass' pasture as appropriate pasture management techniques are developed for this type of pasture. The impetus for this move is the cost (of N fertiliser) and problems with acidification of soil.