Volume 27, 335

Tropical Grasslands (1993) Volume 27, 335–343

Tropical pasture establishment.
7. Sowing methods for pasture establishment in northern Australia

S.J. COOK¹, R.L. CLEM², N.D. MacLEOD¹ and P.A. WALSH³

¹Division of Tropical Crops and Pastures, CSIRO, Brisbane
²Department of Primary Industries, Biloela, and
³Toowoomba, Queensland, Australia

Abstract

A wide range of sowing methods and machinery are used for sowing pastures in northern Australia. In many cases, the sowing method is a compromise between agronomic desirability, practicality and the desire to minimise establishment costs. The most important 2 processes in pasture establishment are the amount of seed which germinates and emerges, and the number of those seedlings which develop into mature plants. In an environment characterised by high levels of evapotranspiration over summer, the amount and distribution of rainfall following sowing have a major influence on pasture establishment. Survival and growth of seedlings are also influenced markedly by competition from established plants. This paper discusses the choice of sowing method and how it can influence the processes of germination-emergence and seedling survival. Sowing methods that provide good soilseed contact and place seed at an optimum depth in the soil can maximise germination and emergence and provide for the efficient use of seed. The need for reliable sowing methods is emphasised. Sowing methods which control plant competition and facilitate soil moisture storage partially reduce problems of unreliable pasture establishment associated with variable rainfall.