Browsing of Antelope Bitterbrush(Purshia tridentata: Rosaceae) in the South Okanagan Valley, British Columbia: Age Preferences and Seasonal Differences
| Autor: | P. G. Krannitz, S. L. Hicks |
|---|---|
| Rok vydání: | 2000 |
| Předmět: |
Ecology
ved/biology Rosaceae ved/biology.organism_classification_rank.species symbols.heraldic_supporter food and beverages Purshia tridentata Biology biology.organism_classification Shrub Twig Agronomy Shoot symbols Ecology Evolution Behavior and Systematics Ovis canadensis Woody plant Odocoileus hemionus hemionus |
| Zdroj: | The American Midland Naturalist. 144:109-122 |
| ISSN: | 1938-4238 0003-0031 |
| Popis: | We compared browsing on twigs of small and large antelope bitterbrush (Purshia tridentata) shrubs among ten sites in the south Okanagan valley, British Columbia. We tested whether there were any age preferences by browsers and determined whether these preferences changed between seasons and mode of browsing. Two different types of browsing were observed: leaf stripping which occurred in the summer and twig clipping which occurred predominantly in the winter. We calculated age and size relationships showing that shoot volume and especially stem diameter were good predictors of shrub age. Among the ten sites, clipping removed 0.02 to 15.7% of a shrub's total twig length and stripping removed leaves from 0 to 5.2% of total twig length. Observations suggested that California bighorn sheep (Ovis canadensis california) stripped antelope bitterbrush leaves in late summer, mule deer (Odocoileus hemionus hemionus) clipped twigs in the winter and cattle clipped twigs in the summer. Browsers preferred to cl... |
| Databáze: | OpenAIRE |
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