Research Branch Report No. 188
Evaluation of herbicides for stem injection of woody weeds in young radiata pine plantations. G. Minko and D. W. Flinn. January 1982. 10 pp. (unpubl.)
SUMMARY
Five herbicides (25% a.i.† hexazinone as Velpar L†††, 20% a.e.†† dicamba as Banvel 200†††, 36% a.e. triclopyr amine as Garlon M/3724†††, 48% a.e. triclopyr ester as Garlon 480 Herbicide†††, and 50% a.e. MCPA amine as Thistle Killem†††) were evaluated for control of silver wattle (Acacia dealbata Link) and several eucalypt (Eucalyptus) species in young plantations of radiata pine (Pinus radiata D. Don), using a stem injection technique. Each herbicide was injected in either spring or winter at three concentrations: undiluted product (100%), 1 part product to 1 part water (50%), and 1 part product to 3 parts water (25%).
Injection in spring of all undiluted herbicides caused high mortality of the target species, although eucalypts appeared more susceptible than silver wattle. Velpar L, Garlon M/3724 and Garlon 480 Herbicide were also effective in a diluted form when injected in spring. These three herbicides, depending on the concentration used, where the only treatments that resulted in high mortality of the target species when injected in winter.
Any other herbicides evaluated in this study could be used to effectively control silver wattle and/or eucalypt species within the size range investigated (about 7 m tall and 3-4 cm DBHOB (diameter at 1.3 m above ground)), provided attention was given to season of injection and product concentration. The choice of herbicide is likely to be dictated more by availability of product, season of injection and toxicological considerations, than by the cost of the product.
† Active ingredient.
†† Acid equivalent.
††† Registered trade name. Use of this product does not in any way constitute an endorsement or recommendation of the product at the exclusion of other, possibly equally suitable products.
Also published:
Minko, G. and Flinn, D.W. (1981) Evaluation of herbicides for stem injection of woody weeds in young radiata pine plantations. Aust. For. 44 (4): 260-6.