The relationship between energy intake and metabolic requirements of beavers {Castor canadensis) is discussed in regard to the spatial requirements of three colonies. A 26pound yearling beaver requires 850 kcal of digestible energy, or 1.5 lb of fresh aspen per day, to maintain its daily metabolic processes with no additional growth. In order for such a beaver to attain maximum growth, 2040 kca...

Altered species interactions are difficult to predict and yet may drive the response of ecological communities to climate change. We show that declining snowpack strengthens the impacts of a generalist herbivore, elk (Cervus elaphus), on a common tree species. Thick snowpack substantially reduces elk visitation to sites; aspen (Populus tremuloides) shoots in these areas experience lower browsin...

The effects of different environmental conditions on the wetting properties and surface morphology of surperhydrophobic quaking aspen leaves harvested during the 2011 growth season are examined. During this particular season quaking aspen leaves were not able to retain their superhydrophobic properties and associated surface structure features as they have usually been able to do in other years...

Aspen are thought to be declining in this region due to a combination of fire suppression, grazing and wildlife management practices, and potentially cool/wet climates of the past century which favor advancing conifer succession. Many scientists are concerned that aspen’s related species may also be losing habitat, thereby threatening the long-term local and regional viability of this important...

We studied the effect of high ozone (O(3)) concentration (110-490 nmol mol(-1)) on regenerating aspen (Populus tremuloides) and maple (Acer saccharum) trees at an open-air O(3) pollution experiment near Rhinelander WI USA. This study is the first of its kind to examine the effects of acute O(3) exposure on aspen and maple sprouts after the parent trees, which were grown under elevated O(3) and/...

Dilute acid (DA) and Sulfite Pretreatment to Overcome Recalcitrance of Lignocelluloses (SPORL) pretreatments were directly applied to wood chips of four poplar wood samples of different genotypes (hereafter referred to as poplars; Populus tremuloides Michx. ‘native aspen collection’; Populus deltoides Bartr. ex Marsh Populus nigra L. ‘NE222’ and ‘DN5’; P. nigra Populus maximowiczii A. Henry ‘NM...

Larval performance of the cottonwood leaf beetle,Chrysomela scriptaF., was evaluated in relation to genetic variation in phytochemical characteristics among Þrst year micropropagated ramets of Þve aspen clones (Populus tremuloidesMichx.). Foliage from the juvenile ramets used in this experiment exhibited moderate variation in nitrogen, phenolic glycosides, and condensed tannin concentrations am...

Automated planning technologies show great promise of reducing operations costs by automating the spacecraft mission planning process. However, one of the bottlenecks is acquiring spacecraft operations knowledge from operations personnel and expressing it in a plan model. One of the primary design goals of the ASPEN planning language is to eliminate the knowledge acquisition bottleneck by makin...

Fine-scale biodiversity is increasingly recognized as important to ecosystem-level processes. Remote sensing technologies have great potential to estimate both biodiversity and ecosystem function over large spatial scales. Here, we demonstrate the capacity of imaging spectroscopy to discriminate among genotypes of Populus tremuloides (trembling aspen), one of the most genetically diverse and wi...

• Extension • Research • Consulting • PHOTO 1. Boreal mixedwood stand where both aspen and white spruce are within the dominant and co-dominant crown classes. Mixed species stands provide options for creating a wide variety of future stand conditions. Forest managers are increasingly being asked to consider and apply a diversity of silviculture systems to address the variety of social, economic...