Low cost overdrilling technology for pasture establishment

Abstract

A prototype strip seeder was developed to establish grasses and legumes in the semi-arid and montane environments of the Mackenzie Basin and Central Otago. Specifications of the strip-seeder required for cost-effective performance were identified on the basis of previous direct drilling investigations in this environment, and included: (a) removal of a strip of existing vegetation to reduce competition; (b) creation of seed bed tilth; (c) controlled and separate placement of seed and fertiliser; and (d) compaction of the drilled seed bed to enhance contact between seed and soil. The prototype strip seeder was built around a modified Duncan 730 multi-seeder chassis, and was used to install spring and autumn trials at Eamscleugh in Central Otago and at Ohau Downs in the Mackenzie Basin. Mechanical improvements were made as the trials progressed. The experience gained, and results from the trials, confirm the suitability of the prototype strip seeder concept for successfully introducing grasses and legumes into this terrain. Keywords direct drilling, strip seeder, seed placement, seed depth, sowing depth