Brushing And Grazing Effects On Lodgepole Pine Vascular Plants And Range Forage In Three Plant Communities In The Southern Interior Of British Columbia

A series of research trials established in 1986-87 in the Kamloops Forest Region, British Columbia, studied the effectiveness of chemical and manual treatment methods for controlling competing vegetation, and also studied the impact that these brushing methods had on the range resource in the region. This report first describes the study methodology, including site selection, experimental design, measurements made, and statistical analyses. It then reports the results of the three studies in the series: the effects of brushing and grazing on lodgepole pine, the dry alder plant community, and range forage at the Devick Lake site; effects of brushing and grazing on lodgepole pine, the willow plant community, and range forage at the Ellis Creek site; and effects of brushing on lodgepole pine, the pinegrass plant community, and range forage at the Upper McKay Creek site.

This handbook contains information on the effects of operational brushing treatments on conifers & plant communities in the Kamloops and Nelson forest regions of British Columbia. Data were collected over a nine-year period from 96 individual PROBE (PRotocol for Operational Brushing Evaluations) trials. The first three sections present an introduction to the PROBE program, its objectives, and the research methodology. Sections 4 to 11 contain detailed analyses for eight vegetation complexes (fireweed, fern, mixed shrub, ericaceous shrub & subalpine herb, dry alder, wet alder, aspen, and mixed broadleaf/shrub complex). Each of these sections contains an abstract, an introduction, site descriptions, results, discussion, conclusions, and management implications. The final section is an overall summary and management recommendation. Appendices include information about the willow and pinegrass complexes, a summary of results for unreplicated treatments involving those communities, and summary tables of information about PROBE sites that presently represent unreplicated treatment cells.

Dry, pinegrass-dominated sites in the interior Douglas fir (IDF) zone of southern interior British Columbia are challenging to regenerate, despite ongoing improvements in nursery & silviculture practices. Using results from three separate studies, this report discusses conifer seedling survival & growth responses to silvicultural systems & site preparation treatments that were applied to relieve harsh site conditions at Fehr Mountain, Murray Creek, and Opax Mountain. To help interpret these responses, the effects of silvicultural system & site preparation treatments on seedling microenvironment are also analyzed with reference to the following factors: soil water, air temperature, soil temperature, light, nutrient availability, soil physical properties, and ectomycorrhizae.

Describes a research trial established in 1986 in southern interior British Columbia to study the effectiveness of glyphosate applied at three and at six litres/hectare, and of manual cutting, to release naturally regenerated lodgepole pine seedlings and suppress dry alder complex. Pine seedlings and two target species, Sitka alder and fireweed, were assessed for the first three years and again in the ninth year following treatment. Measurements made on the seedlings included height, current-year height increment, and stem diameter at root collar. Target vegetation was assessed for species-specific percent cover and the height of one average target specimen per woody species was also measured.

In 1988, three studies were established as part of Experimental Project 995 to study lodgepole pine (Pinus contorta var. latifolia) survival and growth responses to site preparation in the Sub-Boreal Spruce zone of north-central British Columbia. The project examines the effectiveness of several mechanical treatments and localized high-intensity burning, with a focus on disc trenching, which is the most commonly used mechanical site preparation technique in this region. The importance of disc trench orientation, planting aspect, and planting position were investigated, as well as potential interactions between broadcast burning and disc trenching. This report presents 25-year results for the Bednesti North and Bednesti South experiments, and 19-year results for the Tanli experiment. Treatment effects are discussed in relation to: lodgepole pine establishment (survival and early growth to age 5); performance at approximately free-growing age (9 years); and early mid-term growth, stand volume, and site index (as measured at age 25). Of the mechanical treatments tested, coarse mixing was the most effective, resulting in approximately 1-m gains in lodgepole pine height over the control at age 25. This treatment is not practical from an operational perspective, however, and the more common technique of disc trenching with trees planted at the hinge produced the second greatest gains. In contrast, pine planted in trench furrows showed a trend of reduced growth relative to the control. Trench orientation was relatively unimportant, but there was a slight advantage to avoiding north-aspect planting positions. Although broadcast burning alone did not have a significant effect on pine growth, it consistently interacted with disc trenching to produce a mild magnification of responses to that treatment. Pine planted in long, narrow, intensely burned windrow strips were consistently larger than control pine throughout the 25-year assessment period, but they had poor form due to being essentially open-grown.