Treesearch

Provides current information on lumber and plywood production and prices; employment in the forest industries; international trade in logs, lumber, and plywood; volume and average prices of stumpage sold by public agencies; and other related items. Current data and downloadable Excel files are available online.

There is little infonnation available on the long-term effects of managing western redcedar (Thuja plicata Donn ex D. Don). In a 15- to 20-year-old naturally regenerated second-growth redcedar stand on a poor site on the Olympic Peninsula of Washington, we tested crop tree (largest 250 trees/ha) response to precommercial thinning and fertilization in a replicated study. Fertilization treatments were N or N+P applied at study installation and year 13; precommercial thinning occurred at installation. Precommercial thinning without fertilization produced a sustained increase in periodic...

The functional roles of fungi in recovery of forest ecosystems after fire remain poorly documented. We observed macrofungi soon after fire at two widely separated sites, one in the Pacific Northwest United States and the other in southeastern mainland Australia. The range of species onsite was compared against macrofungi reported after the volcanic eruption at Mount St. Helens, also in the Pacific Northwest. Each of the three sites shared species, particularly representatives of the genus Anthracobia. Soon after disturbance, we noted extensive mycelial mats and masses of fruit-bodies of...

Keen's myotis (Myotis keenii) has one of the most limited geographic distributions of any species of bat in North America. Because there is little knowledge of its roosting ecology, we examined selection of day-roosts in trees by male and female Keen's myotis at three spatial scales (tree, tree plot, and landscape) on Prince of Wales Island, southeastern Alaska, from May to September 2006. We selected variables known to influence roost selection by other tree-roosting bats for logistic regression models. We used Akaike's information criterion to rank all models within and between scales...

The stable carbon (C) composition of tree rings expressed as 𗉝C, is a measure of intrinsic water-use efficiency and can indicate the occurrence of past water shortages for tree growth. We examined 𗉝C in 3- to 5-year-old rings of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees to elucidate if decreased water supply or uptake was a critical factor in the observed growth reduction of trees competing with understory herb and shrub vegetation compared to those growing without competition. We hypothesized that there would be no differences in 𗉝C of earlywood in trees...

Seedling establishment is an important factor dictating the altitudinal limits of treeline species. Factors that affect seedling mortality and survival, however, have yet to be fully characterized, especially for deciduous treeline species. Here we describe microsite characteristics of successfully established Betula litwinowii seedlings at the alpine-treeline ecotone. Possible harmful effects of sky exposure on seedling physiology (i.e., photoinhibition of photosynthesis) were also examined, as well as possible facilitative effects of co-occurring Rhododendron caucasicum shrubs on...

Antelope bitterbrush (Purshia tridentata Pursh DC; Rosaceae) is an arid-land shrub that occupies an important ecological niche in various fire-dominated communities across much of the Western United States. Because of its importance as a browse for large mammals and a food source for granivores, P. tridentata is frequently planted by federal agencies in arid-land revegetation. We are currently analyzing the range-wide genetic diversity of this species as part of a larger effort to develop seed movement guidelines. In this study, we describe the development of eight novel nuclear microsatell...

In this study, a travel cost model is used to estimate the value of elk viewing at the Jewell Meadows Wildlife Area in Oregon. Jewell Meadows was originally established to provide winter browse and supplemental feeding for elk to reduce damage to nearby agricultural and forest land. However, because visitors are virtually guaranteed the opportunity to see large numbers of elk at close range, Jewell Meadows has also become a popular wildlife viewing site. We estimated total access value for the 2007 winter feeding season to be $6.5 million, which exceeds Jewell Meadows' annual operating...

We evaluated effects of belowground competition on morphology of naturally established coast Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) saplings in 60- to 80-year-old thinned Douglas-fir stands in southwestern Washington. We separately quantified belowground competition from overstory and understory sources using trenching and understory removal. In this light-limited environment of 26 ± 16 percent (std. dev.) full sunlight, 2-year exclusion of tree root competition by trenching increased sapling stem biomass by 18 percent, total aboveground biomass by 21 percent,...

Fraser fir (Abies fraseri (Pursh) Poir.) is an endemic tree species found only in refugial mountain-top forests in the southern Appalachian Mountains, USA. Very few studies have investigated the ecophysiology of this species in its natural environment. We measured and compared photosynthetic gas exchange and water relations of understory germinant seedlings 3 years old and ~0.15 to 1 m tall), and saplings (>10 years old and ~1 to 2 m tall) on a leaf-level basis. No significant differences in gas exchange were found among the age classes, although midday xylem water potentials were significa...