Screening of herbicides for stem injection of cull trees in a eucalypt forest.  G. Minko and L. A. Stephens.  December 1985.  6 pp. (unpubl.)

SUMMARY

Six herbicides (dicamba as BANVEL 200^®, triclopyr amine as GARLON M/3724, triclopyr ester as GARLON 480, glyphosate as ROUNDUP, hexazinone as VELPAR L, and dicamba derivative as VELSICOL 4092) were evaluated for control by stem injection of large, defective eucalypt trees (culls) in a mature eucalypt forest.

Injections of glyphosate as undiluted ROUNDUP at 1 mL per 7 cm of stem circumference caused 100% mortality of the five eucalypt species included in the study. The other five herbicides were effective when injected at the same rate in undiluted form to control red box (Eucalyptus polyanthemos Shauer), but produced variable results when applied to the more resistant species of broadleaved peppermint (E. dives Shauer), narrowleaf peppermint (E. radiata Sieber ex DC.), red stringybark (E. macrorhyncha F. Muell. ex Benth.) and long-leaf box (E. goniocalyx F. Muell. ex Miq.).

Stem injection of glyphosate as undiluted ROUNDUP will kill large cull trees of the five eucalypt species tested. Other herbicides may be equally useful when applied to the most susceptible eucalypt species identified in this study. Therefore, stem injection with herbicides may be a useful means of killing cull trees that are either preventing the establishment of regeneration, or excessively inhibiting the growth of existing regeneration.

^®Registered Trade Name. Use of trade names does not constitute official endorsement or approval by the Department of Conservation, Forests and Lands.

Also published:

Minko, G. and Stephens, L.A. (1985)  Screening of weedicides for stem injection of cull trees in a eucalypt forest.  Weed Talk 2: 3-4.