Aspen Bibliography
Porcupine Mountain Herbicide Trial
Document Type
Report
Publisher
The Canadian Forest Service
Publication Date
1994
Abstract
White spruce plantations have been established within the Mixedwood Section of the Boreal Forest (B.18a) (Rowe 1972) of Manitoba to provide a necessary long term supply of white spruce sawlog material. Trembling aspen competition within these plantations will have a devastating effect on potential spruce sawlog yields if it is not controlled. The objectives of this study were to evaluate the herbicidal and silvicultural efficacy of aerial applied Roundup· (glyphosate) in a white spruce plantation in the Mixedwood Section (B.18a) of the boreal forest of western Manitoba. The objective was met by conducting aerial applications of Roundup· at four rates. The trial was established within a white spruce plantation located in the Porcupine Provincial Forest of western Manitoba. The study area was burned-over in May 1980, site prepared with a disc trencher (ITS-350) in September 1981 and hand planted in May 1982 with 3+0 white spruce seedlings. Data was collected in 1984, 1985, 1986, and 1993.
Roundup· affected both the trembling aspen and white spruce in a desirable manner. Trembling aspen mortality increased as the rate of Roundup· increased from 2.5 to 5.6 L/ha. White spruce showed a positive growth response within two growing seasons after the application of Roundup·. Although relatively small gains in survival and height growth of white spruce were realized, the greatest gains were related to diameter and volume growth. Under favourable circumstances, 2.5 L/ha was sufficient to release white spruce from the trembling aspen competition. Higher rates (i.e., 4.5 L/ha) should be considered if snowshoe hare poses a serious threat to a plantation, if weather conditions are less than favourable at the time of application or if high number of logging residuals are present.
Recommended Citation
Ardron, G. et al. 1994. Porcupine Mountain herbicide trial.
Comments
Canada-Manitoba Partnership Agreement in Forestry Contribution Agreement 4003, Final Report submitted to The Canadian Forest Service.