Aspen Various, Populus

Triazine herbicides are primarily effective in controlling herbaceous weeds. A notable exception is the use of granular hexazinone for controlling woody invaders such as oaks (Quercus spp.) or aspen (Populus tremuloides) in conifer stands on medium- and fine-textured soils in the South or in boreal forests. Hexazinone also is used in the Maritime Provinces of Canada for controlling woody and herbaceous growth in natural Christmas tree stands (Townsend, 1995a). The impact of herbaceous plant cover is somewhat different from that of woody plant competitors, so control strategies on various forest conifer sites may differ. 

Fig. 7.17 First-instar survival and penultimate-instar growth performance RGR = relative growth rate ECI = overall efficiency of conversion of ingested plant biomass) on quaking aspen, Populus tremuloides of various populations of P. glaucus canadensis and P. g. glaucus as a function of geographical proximity to the range of the host plant.

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