Treesearch

Using the NASA Earth Exchange platform, the North American Forest Dynamics (NAFD) project mapped forest history wall-to-wall, annually for the contiguous US (1986-2010) using the Vegetation Change Tracker algorithm. As with any effort to identify real changes in remotely sensed time-series, data gaps, shifts in seasonality, misregistration, inconsistent radiometry and cloud contamination can be sources of error. We discuss the NAFD image selection and processing stream (NISPS) that was designed to minimize these sources of error. The NISPS image quality assessments highlighted issues with...

Information on the foraging ecology of animals is important for conservation and management, particularly for keystone species whose presence affects ecosystem health. We examined foraging by an at-risk cavity excavator, the white-headed woodpecker (Picoides albolarvatus). The foraging needs of this species are used to inform management of ponderosa pine (Pinus ponderosa) forests in some areas of western North America. Past observational studies indicated that white-headed woodpeckers forage predominately on cones and trunks of large-diameter (>68 cm) pines in old-growth stands, although...

The extreme precipitation event on October 3-4, 2015, likely resulting from the convergence of a persistent the terrain, and thecirculation associated with Hurricane Joaquin off the eastern Atlantic Coast(http://cms.met.psu.edu/sref/severe/2015/04Oct2015.pdf) resulted in extreme present the precipitation amounts and intensities observed at four gauges on the USDA Forest Service Santee Experimental Forest (SEF) watersheds during this extreme event in conjunction with the antecedent conditions for 5 days prior to the event. All four rain gauges recorded 24-hr maximum rainfall of 340 mm or...

The walnut twig beetle [WTB (Pityophthorus juglandis Blackman)] is the primary insect vector for a pathogen that causes thousand cankers disease (TCD), a disease complex that leads to mortality in species of walnut (Juglans L.). We performed field and laboratory trials to determine if reproduction by WTB varies between two black walnut (Juglans nigra L.) parent trees of a full-sib mapping population of 323 offspring, and between black walnut and butternut (Juglans cinerea L.). These two tree species are native to eastern North America. In field trials, we found no significant differences...

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,...