Effects of 2,2-DPA, ripping and oversowing on pasture yield and composition

Abstract

Four rates of 2,2-DP A (2,2-dichloropropionic acid) were used in conjunction with ripping and oversowing of additional white clover (Trifolium repens) to rejuvenate rain-grown clover pastures invaded by mat grass (Axonopus affinis) at Cooroy in south-east Queensland. Herbicide treatment applied between June and July 1971 markedly increased clover yield in May and July 1972, and decreased mat grass yield in May 1972. By November 1972 the herbicide's effect had worn off. Clover or mat grass yields were insensitive to herbicide application rates. Oversowing did not confer any benefits under the prevailing weather conditions, but there was a suggestion of benefit from ripping on clover yield in the absence of herbicide application.