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T. Weaver

Publications and source records attributed to T. Weaver.

2 recordsLinked to original sources

A rule-based model for mapping potential exotic plant distribution

Wildland managers need a method to predict which portions of the lands under their stewardship are susceptible to invasion by exotic plants. We combined a database listing exotic plant species known to occur in major environmental types (habitat types) throughout the northern Rocky Mountains with a digital vegetation map of environmental types for a major national park in the region (Yellowstone National Park) to produce maps of areas potentially threatened by major exotic species. Such maps should be helpful to managers concerned with monitoring and controlling exotic plants.

Western North American Naturalist↗

Berry production in three whitebark pine forest types

In the whitebark pine /whortleberry ( Pinus albicaulis/Vaccinium scoparium ) habitat type of southwestern Montana, whortleberry plants produced seven to 69 berries/m2 x yr in 1974. In subalpine fir ( Abies lasiocarpa ) habitat types of northwestern Montana, huckleberry plants ( Vaccinium globulare ) may produce from 13 to 228 berries/m2 X yr. While removal of competing trees increases production, thinning the understory apparently reduces berry production in direct proportion to the shrubs removed; there is no compensatory production indicative of shrub-shrub competition in fully vegetated plots. Fifty-to 100-fold variation in production among years in Vaccinium globulare berry production is attributed to variation in weather conditions.

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