Methods of establishing tall fescue and ryegrass in a dryland environment

Abstract

Optimal systems for establishing new pastures were considered at trial sites in southern Hawkes Bay and Manawatu. Systems of pasture establishment, before drilling new pasture in autumn, were: (a) spring sown barley, (b) summer fallow by cultivation, (c) summer fallow by glyphosate spraying, and (d) pasture during summer then a single glyphosate spray at drilling. Each establishment treatment was sown with white/sub clover, and either tall fescue (an example of a dryland grass species) or perennial ryegrass. Methods (a) and (b) used a roller drill to sow pastures into a cultivated seedbed, and methods (a), (c) and (d) used a direct drill. A very moist cool summer resulted in no advantage to the fallow treatments in terms of better soil moisture at sowing, but generally these treatments had the best establishment, possibly due to low weed contents and higher soil nitrogen levels. A single spray with glyphosate before direct drilling gave the poorest results for both grass species. The relative advantages and disadvantages of each treatment are discussed. Establishment and yields of tall fescue were lower than for ryegrass, although tall fescue had higher white/sub clover contents and less dead matter than ryegrass pastures. A low sowing rate and colder-than-average temperature at sowing may have depressed the establishment of tall fescue. Ryegrass quickly recovered from lower levels of establishment (within 3-6 months) but tall fescue took 9-12 months to show any improvement in contribution to pasture yields. Keywords: dryland, Festuca arundinacea, L.&urn perenne, pasture establishment