Establishment and persistence of palatable taxa of Eragrostis curvula complex in southern New South Wales

Abstract

Summary. Spring sowings in cultivated plots at Wagga Wagga in 1980 and 1982, and Cowra and Colinroobie in 1980 and 1981 examined the establishment and persistence of Eragrostis curvula (Schrad.) Nees complex cv. Consol and accession 4660, Cenchrus ciliaris L. cv. American and Phalaris aquatica L. cv. Sirocco. Cenchrus ciliaris was short-lived and not frost-hardy. Competition and dry conditions reduced establishment of all species, nevertheless E. curvula established reliably. In 1 experiment where conditions were not immediately favourable for germination, E. curvula demonstrated a capacity to delay establishment until conditions improved. Competition from cool-season plants reduced persistence, particularly in the first year and when conditions were dry. Surviving E. curvula plants were generally long lived. At Cowra, the density of E. curvula was enhanced by regular mowing, but mowing reduced the density of P. aquatica. Presence of Trifolium subterraneum L. reduced the density of E. curvula while P. aquatica was unaffected.

A second experiment at Colinroobie, sown in October 1987 examined the effects of mowing and fertiliser application on establishment and persistence of E. curvula cv. Consol and accession 4660. Fertiliser increased competition by cool-season annual species, reducing establishment and persistence of E. curvula, while regular mowing improved its persistence. In an experiment sown at Wagga Wagga in October 1989, E. curvula cv. Consol establishment was very low (<1 plant/m²) in undisturbed annual pasture and in the absence of cultivation, herbicide (glyphosate at 530 g a.i./ha) and mowing with herbage removal provided the best conditions for establishment.