Effect of resident vegetation on establishment of surface sown pasture species at Glen Innes, New South Wales

Abstract

The influence of resident vegetative cover on the establishment of surface sown seed was determined in a field experiment at Glen Innes, New South Wales. Seed was sown on 25 occasions over a period of 2 years spanning the period November 1969 to January 1972. Species sown were Phalaris aquatica, Festuca arundinacea, Medicago sativa and Trifolium subterraneum. The relationship between mean per cent establishment and vegetative cover was significant and was described by the quadratic equation y = 0.8064 ¦ 9.8342x - 0.8829x2. Presence of vegetative cover significantly increased mean establishment on 22 occasions. Presence of Sorghum leiocladum plants as a component of the resident vegetation had a larger influence on establishment of surface sown species than Bothriochloa ambigua and Poa sieberana. It was concluded that the best means of obtaining maximum establishment of surface sown pasture species in native grassland areas on the Northern Tablelands of New South Wales was by sowing into vegetative cover (approximately 5000 kg ha-1) and sowing during the period May-July.