study examines the medicinal uses of 4 plants (red-osier dogwood (cornus stolonifera) ; fireweed (epilobium angustifolium) ; bracken fern (pteridium aquilinum) and red raspberry (rubus idaeus). it also examines the impact of the herbicides glyphosate and triclopyr on them.vegetation management to release conifers from competing angiosperms is practiced throughout canada. aerial herbicide application, mechanical cutting, and site preparation are some of the techniques used to suppress competing vegetation. scientific evidence demonstrates that these techniques allow conifers to establish in the first few years after planting. one of the issues that arise, especially from the public, is concern that aerial herbicide applications have on other values. hence, there is pressure on managers to find alternatives for the chemical control of vegetation that hinders early conifer growth. in this thesis, the abundance in distribution of cornus, epilobium, pteridium, and rubus was computed, seven years after the silvicultural treatments were applied in the area. all four species studied show potential medicinal ingredients both from ethnobotanical, and pharmaceutical perspectives. a single application of herbicides or mechanical treatments did not show any statistical difference from the control plots in the abundance of the above species. however, the trends show slight variation. by using mechanical methods for controlling these species, the medicinal values can be made available for development by the pharmaceutical companies, without contributing to any environmental degradation that may result from aerial herbicide application.