Subsampling and subsequent imputation of tree heights can improve the predictive performance of stand volume estimation but may also introduce biases. Using coastal Douglas-fir data from southwest Oregon, USA, the predictive performance of several height imputation strategies for estimating stand volume was evaluated. A subsample of 1-15 trees was randomly...
Using an extensive Douglas-fir data set from southwest Oregon, we examined the (1) performance and suitability of selected prediction strategies, (2) contribution of relative position and stand-density measures in improving tree height (h) prediction values, and (3) effect of different subsampling designs to fill in missing h values in a...
The effects of prescribed underburning on soil total C pools, total and inorganic N pools, and in situ net N mineralization were examined during a 1-year study in ponderosa pine (Pinus ponderosa Dougl. ex P. & C. Laws.) sites that had been experimentally burned 4 months, 5 years, or 12...
One of the challenges often faced in forestry is the estimation of forest attributes for smaller areas of interest within a larger population. Small-area estimation (SAE) is a set of techniques well suited to estimation of forest attributes for small areas in which the existing sample size is small and...
We examined the performance of several generalized linear fixed- and mixed-effects individual-tree mortality models for Douglas-fir stands in the Pacific Northwest. The mixed-effects models accounted for sampling and study design overdispersion. Inclusion of a random intercept term reduced model bias by 88% relative to the fixed-effects model; however, model discrimination...
Total US lumber production in 2011 was 77.9 million cubic meters. Its primary use was for housing and construction. There is a growing concern that the structural properties for wood are being reduced as trees are harvested at much younger ages as the wood supply shifts from older to younger...
Microclimate variables such as air temperature and relative humidity influence habitat conditions and ecological processes
in riparian forests. The increased relative humidity levels within riparian areas are essential for many plant and wildlife
species. Information about relative humidity patterns within riparian areas and adjacent uplands are necessary for the
prescription...
Managers use restorative fire and thinning for ecological benefits and to convert fuel-heavy forests to fuel-lean landscapes that lessen the threat of stand-replacing wildfire. In this study, we evaluated the long-term impact of thinning and prescribed fire on soil biochemistry and the mycorrhizal fungi associated with ponderosa pine (Pinus ponderosa)....
The degree to which carbon concentration (CC) of woody detritus varies by tree taxa, stage of decay, tissue
type (i.e., bark versus wood), and vertical orientation was examined in samples of 60 tree species
from the Northern Hemisphere. The mean CC of 257 study samples was 49.3% with a range...
The National Forest System (NFS) of the United States plays an important role in the carbon cycle because
these lands make up a large proportion of the forested land in the country and commonly store more wood
per unit area than other forest ownerships. In addition to sustaining natural resources,...
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forest
type group, and default inclination adjustment from Woodall and
Monleon (2008), and the weighted