Treesearch

There is considerable interest in evaluating whether recent wildfires in dry conifer forests of western North America are burning with uncharacteristic severity - that is, with a severity outside the historical range of variability. In 2002, the Hayman Fire burned an unlogged 3400 ha dry conifer forest landscape in the Colorado Front Range, USA, that had been the subject of previous fire history and forest age structure research. We opportunistically leveraged pre-existing data from this research, in combination with post-fire aerial imagery, to provide insight into whether the Hayman...

Fusarium species, specifically F. commune, F. proliferatum, and F. solani, can cause severe damping-off and root disease in container and bareroot forest nurseries throughout North America. Many conifer and hardwood species can be affected, but Douglas-fir (Pseudotsuga menziesii), western white pine (Pinus monticola), and ponderosa pine (P. ponderosa) are known to be susceptible to Fusarium root disease (Stewart et al. 2012).

Management of regulated rivers for yellow-legged frogs (Rana boylii) and salmonids exemplifies potential conflicts among species adapted to different parts of the natural flow and temperature regimes. Yellow-legged frogs oviposit in rivers in spring and depend on declining flows and warming temperatures for egg and tadpole survival and growth, whereas salmonid management can include high spring flows and low-temperature reservoir releases. We built a model of how flow and temperature affect frog breeding success. Its mechanisms include adults selecting oviposition sites to balance risks of...

The ability to identify individual animals is a valuable tool in the study of amphibian population dynamics, movement ecology, social behavior, and habitat use. Numerous methods of marking amphibians have been employed including the use of passive integrated transponder (PIT) tags, radio-transmitters, elastomers, branding, and mutilation techniques such as toe-clipping (Ferner 2007). All of these methods are invasive to amphibians to some degree and can alter their behavior, decrease recapture rates, reduce survivorship, and even cause direct mortality in some cases (Ferner 2007). One of...

Hieracium spp. (Asteraceae) are noted for their taxonomic complexity, frequent incidence of apomixis and polyploidy, and invasive tendencies. Here we report the Eurasian taxa, Hieracium caespitosum Dumort. and Hieracium piloselloides Vill., as recent additions to the flora of South Dakota. Plants were collected at three locations in the Black Hills during 2014 and 2015 and compared to specimens of H. caespitosum and H. piloselloides at major herbaria (RM, MO, SDC) for five morphometric traits. We found significant differences (P<0.05) between previously identified specimens of these...

We held a workshop related to the use of emerging technology to understand the ecology of grouse on 03 September 2015 from 08:00 to 17:30 at the Reykjavik Family Park and Zoo, Reykjavik, Iceland as part of the 13th International Grouse Symposium. Our overall objective was to translate technological advances in remote sensing, rapid biochemical assays, and robotics to resource managers for improved understanding, monitoring, and management of wildlife habitat and behavior in a changing climate. The workshop included seminars and hands-on demonstrations of equipment used to collect, analyze,...

Every year wildland fires affect much more acreage in the United States compared to controlled burns. Like controlled burns, wildland fire can help promote biological diversity and healthy ecosystems. But despite these facts, wildland fire is not often considered as a fuel treatment in the United States. Scientists working with the U.S. Forest Service’s Rocky Mountain Research Station have evaluated more than 40 years of satellite imagery to determine what happens when a fire burns into a previously burned area. Results from this research are helping land managers to assess whether a...

Size reduction homogenizes the bulk biomass and facilitates downstream feedstock handling, transportation, and storage. Effects of feeding rate, mill-type (hammer and knife mill), screen size, and moisture content on comminution energy consumption of commercial Douglas-fir (Pseudotsuga menziesii) pulp chips were quantified. The resulting particles were characterized by geometric mean diameter, size distribution, aspect ratio and bulk density. We also employed scanning electron microscopy (SEM) to visualize the dominant fracture surface features. A linear regression was used to describe the...

The third full cycle of annual inventories (2009-2013) of Missouri's forests, completed in 2013, reports that there are an estimated 15.5 million acres of forest land in the State. An estimated 60 percent of the forest land area is in sawtimber size stands, 30 percent are pole timber size, and 10 percent are seedling/sapling size or nontstocked. The net volume of live trees on forest land increased by 4 percent, from 20.1 million cubic feet in 2008, to 21.0 million cubic feet in 2013. Average annual net growth of live trees on forest land decreased by more than 25 percent, from an average...

To address a need for air quality and lichen monitoring information for the Northeast, we compared bulk chemistry data from 2011-2013 to baseline surveys from 1988 and 1993 in three Class I Wilderness areas of New Hampshire and Vermont. Plots were within the White Mountain National Forest (Presidential Range—Dry River Wilderness and Great Gulf Wilderness, New Hampshire) and the Green Mountain National Forest (Lye Brook Wilderness, Vermont). We sampled epiphyte communities and found 58 macrolichen species and 55 bryophyte species. We also analyzed bulk samples for total N, total S, and 27...