Post-harvesting glyphosate and imazapyr application on Eucalyptus stumps to control coppice. Issue 3 (3rd July 2022)

• Record Type: Journal Article
• Authors: Montes, W. G.; Tuffi Santos, L. D.; Barros, R. E.; de Paiva Ferreira, G. A.; Silva Donato, L. M.; Reis, M. M.; de Oliveira, L. S.
• Is Part Of: Australian forestry. Volume 85:Issue 3(2022)
• Page Start: 97
• Page End: 104
• Publication Date: 2022-07-03
• Subjects: chemical control -- cut-stump control -- Eucalyptus -- shoot eradication -- unwanted shoots; Forests and forestry -- Australia -- Periodicals; Forests and forestry -- Australasia -- Periodicals; 634.90994
• DOI: 10.1080/00049158.2022.2107756
• Languages: English
• ISSNs: 0004-9158

Abstract

ABSTRACT: The objective of this research was to assess the efficiency of applying glyphosate and imazapyr to Eucalyptus cut-stump surfaces after harvesting to control sprouting. Two experiments were conducted in Eucalyptus grandis × Eucalyptus urophylla plantations arranged in a randomised block design with five treatments and five replicates. In experiment 1, 0, 0.84, 1.67, 2.50 and 3.34 kg of acid equivalent (a.e.) ha −1 of glyphosate was applied. Experiment 2 involved the application of 0, 0.028, 0.083, 0.140 and 0.195 kg a.e. ha −1 of imazapyr. The application was carried out between 42 and 48 hours after harvesting in replicates of 36 stumps. Increased glyphosate doses increased coppice control to more than 90%. Coppice was present on approximately 30% of the stumps treated with the highest glyphosate dose. However, these shoots showed low vigour 225 days after application, with mean values of about 0.30 m in height and 0.5 shoots per stump. In the control treatment, coppice reached 3.0 m in height and 8.0 kg green mass weight, and coppice was present on 97% of the stumps. The highest imazapyr doses increased shoot control to 80%. Post-harvesting application to cut stumps reduced coppice development. However, only the glyphosate doses of 2.50 and 3.34 kg a.e. ha −1 presented satisfactory coppice control levels without follow-up operations.