| Popis: |
Q uaking aspen ( Populus tremuloides ) habitats con- tribute to species diversity, provide forage and shade for wildlife and livestock, and are highly valued by humans for their productivity and beau- ty. Aspen decline has been observed in the western United States over the past 50 years and has been mainly attributed to a decrease in re frequency, caused by effective re suppres- sion. 1 Changing re regimes have allowed conifer species to expand into aspen stands. Another phenomenon, commonly referred to as “Sudden Aspen Decline” (SAD), has been ob- served within the past decade in the western mountains and in the Canadian aspen parklands. 2 Mature aspen stems begin to die at rates beyond what is expected, which if aspen regen- eration is limited, can eventually lead to the loss of the aspen roots and stands. Excessive browsing by livestock and wildlife can also inhibit aspen regeneration. DOI: 10.2458/azu_rangelands_v34i5_strand |
