Treesearch

This poster presents the continuing cooperative relationship between the Fort Valley Experimental Forest (FVEF), Coconino National Forest (CNF), USFS Region 3, and the long-term partnerships with the Museum of the Northern Arizona and the NAU School of Forestry.Fort Valley was initially named the Coconino Experiment Station and funds were channeled through Region (then District) 3 and the CNF. CNF Ranger William Wilson assisted G.A. Pearson that first winter at Fort Valley. Since Fort Valley's establishment as an experimental area, Forest Service Research has worked in conjunction with the...

In 1913, the Fort Valley Experimental Forest initiated an unprecedented case-study experiment to determine the effects of harvesting methods on tree regeneration and growth on a ponderosa pine-Gambel oak forest at Coulter Ranch in northern Arizona. The harvesting methods examined were seed-tree, group selection, and light selection. In addition, the effects of livestock grazing (excluded or not) were examined. We revisited the Coulter Ranch Study Site to examine the effects of these treatments on historical (1913) and contemporary (2003-2006) stand density and tree size. The key finding...

When the Riordan brothers of Flagstaff, Arizona, asked Gifford Pinchot to determine why there was a deficit in ponderosa pine seedlings, neither party understood the historical significance of what they were setting in motion for the field of forest research. The direct result of that professional favor was the establishment of the Fort Valley Experiment Station (Fort Valley) in 1908, and the insights produced through its research program are remarkable. The scientists that passed through Fort Valley are an accolade that commonly goes unmentioned, and includes extraordinary individuals...

This paper presents a vascular plant species list for two sites that are part of a long-term study exploring the effects of varying fire intervals on forest characteristics including the abundance and composition of understory vegetation. The Chimney Spring study area is on the Fort Valley Experimental Forest near Flagstaff, AZ, and the Limestone Flats study area is on the Long Valley Experimental Forest, 90 km (56 mi) southeast of Flagstaff. Since 1976 (Chimney Spring) and 1977 (Limestone Flats), three replicates of each of seven burn intervals (1, 2, 4, 6, 8, 10 years, plus unburned)...

Disturbances generated by forest restoration treatments have the potential for enhancing the establishment of nonnative species thereby impeding long-term native plant recovery. In a ponderosa pine forest next to the Fort Valley Experimental Forest, Arizona, we examined the establishment of nonnative species after three alternative treatments with different intensities of tree thinning, coupled with prescribed burning and an untreated control, in relation to total species abundance and richness. Pretreatment data were collected in 1998 and postreatment responses were measured from 2001...

The 1908 founding of the first American forest experiment station in Fort Valley, Arizona was an event of considerable historical significance. The Fort Valley station was the linchpin of forester Raphael Zon's bold plan to create the first program of organized research in U.S. Forest Service history. It also represented the beginning of a fruitful marriage between German and American methods of forestry. This project traces the history of government-run experiment stations from its roots in Vienna, Austria, in the 1870s, through the work of German-American forester Bernhard Fernow and...

Cambium injury is an important factor in post-fire tree survival. Measurements that quantify the degree of bark charring on tree stems after fire are often used as surrogates for direct cambium injury because they are relatively easy to assign and are non-destructive. However, bark char codes based on these measurements have been inadequately tested to determine how well they relate to live or dead cambium. Methods for assessing cambium injury through direct sampling have also been questioned as a potential factor for increasing tree mortality. In this study we used data collected from 11...

The general concept of an open-path backscatter nephelometer, its design, principles of calibration and the operational use are discussed. The research-grade instrument, which operates at the wavelength 355 nm, will be co-located with a scanning-lidar at measurement sites near wildfires, and used for the lidar calibration. Such a near-end calibration has significant advantages compared with the conventional method of far-end calibration that assumes an aerosol-free atmosphere at some high altitude.

A dual-wavelength photoacoustic instrument operating at 405 and 870 nm was used during the 2006 Fire Lab at Missoula Experiment to measure light scattering and absorption by smoke from the combustion of a variety of biomass fuels. Simultaneous measurements of aerosol light scattering by reciprocal nephelometry within the instrument's acoustic resonator accompany photoacoustic aerosol light absorption measurements. Single scattering albedo values at 405 nm ranging from 0.37 to 0.95 were measured for different fuel types, and the spectral dependence of absorption was quantified using the...

Biomass burning is an important source of particulate organic carbon (OC) in the atmosphere. Quantifying this contribution in time and space requires a means of routinely apportioning contributions of smoke from biomass burning to OC. Smoke marker (for example, levoglucosan) measurements provide the most common approach for making this determination. A lack of source profiles for wildfires and prescribed fires and the expense and complexity of traditional smoke marker measurement methods have thus far limited routine estimates of these contributions to ambient aerosol concentrations and...