In Proceedings of the 19th Australasian Weeds Conference, pages 190–193. Paper abstract bibtex
Desert ash (Fraxinus angustifoliaVahl. subsp. angustifolia, Oleaceae) is a weedy deciduous tree in south-eastern Australia, particularly in riparian situations. It reproduces by seed and by root suckers and can form monocultures displacing desirable native shrubs and trees. Very little published information is available regarding suitable control methods and anecdotal reports of the effectiveness of herbicides are variable. We conducted two trials to determine the effectiveness of herbicides to control desert ash. From the first screening trial picloram and triclopyr + picloram were excluded, and the herbicides glyphosate, glyphosate + metsulfuron-methyl, metsulfuronmethyl alone at two rates and triclopyr ester were tested further. Approximately 150 trees were used in a second trial with herbicide treatments applied using the cut and paint method. Glyphosate was the best performing herbicide, with no healthy regrowth arising from stumps at the end of the trial, 35 months after treatment (MAT). Triclopyr ester also performed well with regrowth from 6\,% of treated stumps. The number of stumps with regrowth for the two metsulfuronmethyl treatments and the metsulfuron + glyphosate mix increased over the three year period of the trial, while the number of stumps with regrowth reduced for the glyphosate and triclopyr-treated stumps. Trials are underway to determine the effect of herbicide application method (cut stump, stem injection) and time of application (winter, summer, autumn) on desert ash control.