Weed control techniques for the establishment of Eucalyptus regnans plantations on pasture sites

Abstract

Summary Nine different herbicidal chemicals were applied in 36 different combinations of rate, time and application technique for the control of herbaceous weeds where Eucalyptus regnans (mountain ash) was being planted in South Gippsland. Knock-down and pre-emergence herbicides were applied alone and in mixture, pre—and post-planting, using strip spraying (controlled droplet application) and spot treatment (spotgun and rope-wick wiping) techniques. Twenty-one months after planting, several treatments gave significantly greater height growth than the manually weeded or untreated controls without substantially increased tree mortality. The cheapest, effective pre-planting treatments included amitrole+simazine (2+3 kg ha−1), amitrole+dalapon (2+5 kg ha−1) and glyphosate+simazine (1+3 kg ha−1). Two of the better post-planting treatments were propazine (6 kg ha−1), and propazine+propyzamide (1.5+1.5 kg ha−1), applied to predominantly bare soil. For pre—planting weed control, the study demonstrated the benefit...