D.B. COATES

Division of Tropical Crops and Pastures, CSIRO, Townsville, Queensland, Australia

Abstract

The recovery of Sabi grass (Urochloa mosambicensis) cv. Nixon after an unusually long and severe dry season in 1994, which followed 3 years of below average rainfall, was monitored in 5 experimental paddocks. Sabi grass recovered during the short wet season of 1994/95, despite rainfall being only about 40% of the long-term average, and mean pasture presentation yields exceeded 4 t/ha by mid-March. Sabi grass contributed 48–84% of total yield while broadleaf weeds contributed less than 5%. Recovery of Sabi grass was by a combination of regrowth of established plants and seedling recruitment. Recovery occurred even where most or all established plants had died. At the end of December, after the first effective germinating rain, mean seedling density exceeded 100 plants/m² compared with c. 40 plants/m² for surviving established Sabi grass plants, but there was wide variability between and within paddocks. Plant density at the end of the wet season remained high with mean paddock densities between 110 and 250 plants/m², many being small plants with a single tiller.