Target populations for direct-drilled ryegrass and tall fescue

Abstract

Establishment, botanical composition and production of direct-drilled perennial ryegrass and tall fescue were compared for two seeding rates in an autumn-sown, grazed trial. Tall fescue (Festuca arundinacea Schreb. cv. AU Triumph) was sown at either 17 or 3 1 kg/ha and perennial ryegrass (Lolium perenne L. cv. Grasslands Supernui) was sown at 12 and 23 kg/ha on 12 April, 1990 all with "Grasslands Pitau" white clover at 3 kg/ha. Measurements of herbage mass and botanical composition during the ensuing 2-year period showed that there was no advantage in terms of suppression of weed species or accumulation of herbage mass of the sown species from sowing more seed than that required to achieve a population of 450-500 plants/m2 of either ryegrass and tall fescue 6 weeks after sowing. A population of 150 white clover plants/m2 appeared to be adequate for development of a balanced sward. Establishment of fescue was slower than that of ryegrass but both species developed to productive swards after infrequent but close defoliation with dairy cattle in the first spring and subsequent rotational grazing by lactating dairy cows. Pasture establishment in Northland is difficult because of shallow topsoils. Direct drilling can preserve this fragile topsoil and successfully establish alternative species such as fescue as long as attention is paid to their establishment requirements. Alternative species may offer a solution to low feed availability of ryegmss in the summer and poor survival of ryegrass in poorly drained areas during the winter. Keywords: direct drilling, Festuca arundinacea, Lolium perenne, pasture establishment, seeding rate