Treesearch

Integrated lumber and paper productions using forest thinning materials from U.S. national forests can significantly reduce the cost of prescriptive thinning operations. Many of the trees removed during forest thinnings are in small-diameter classes (diameter at breast height

High-value, large-volume utilization of forest thinning materials from U.S. National Forests is a potentially important contributor to sustainable forest health. This study demonstrated the utilization of wood chips produced from thinnings for the production of thermomechanical pulp (TMP). Both whole-log chips (primarily from small-diameter logs, tops, and reject logs) and sawmill “residue” chips from a Hewsaw system (Mäntyharju, Finland) were evaluated. The residue chips produced in this study were substituted for a TMP mill’s standard residue chips up to about 50%. The whole-log chips...

The carbon dioxide (CO2) concentration of Earth’s atmosphere continues to rise. Plants in general are responsive to changing CO2 concentrations, which suggests changes in agricultural productivity in the United States and around the world. The ability of plants to absorb CO2 during photosynthesis and then store carbon in their structure or sequester it in the soil has potential for mitigating the rate of rise of atmospheric CO2 concentration. Since 1987, Bruce Kimball and coworkers at the USDA Agricultural Research Service in Phoenix, Arizona, have maintained a greenhouse gas experiment...

The sapwood of ochoó (Hura crepitans) suffers from an oxidative stain that results in substantial loss in value, making it one of the most important utilization problems encountered among Bolivian timber species. Initiating kiln drying within 6 days of felling did not reduce staining of ochoó, although many boards with extensive interior stain had bright surfaces, so it is possible that immediate drying might reduce or eliminate discoloration. Shock treatments did not reduce staining either, except for the localized effects of surface hammering. Eighteen-hour treatment with a 5% solution...

This report provides general and statistical information on forest products markets in terms of production, trade, consumption, and prices. The current state of the U.S. economy is described. Market developments are described for sawn softwood, sawn hardwood, softwood log trade, wood-based panels, paper and paperboard, fuelwood, and forest product prices. Policy initiatives that can affect domestic markets and international trade in wood products are also discussed in some detail. Estimates are made through the end of the year 2007.

Using mean values for basic (green) specific gravity and Janka side hardness for individual species obtained from the world literature, regression equations were developed to predict side hardness from specific gravity. Statistical and graphical methods showed that the hardness–specific gravity relationship is the same for tropical and temperate hardwoods, but that the relationship for softwoods is different from that for hardwoods. As expected, the relationship for green wood is different from that for wood at 12% moisture content.

The science of tree stability analysis uses both biological and engineering principles in attempting to rate a tree’s structural soundness and make reasonable predictions of potential for failure. In such analysis, arborists are often challenged by internal structural defects hidden from view within the trunks. This paper reports the results of an investigation using acoustic tomography to detect internal decay in park trees. Two century- old red oak (Quercus rubra) trees located at the Capitol Park in Madison, Wisconsin, were nondestructively evaluated using an acoustic tomography...

This report presents annual data but is published every 2 years. The data present current and historical information on the production, trade, consumption, and prices of timber products in the United States. The report focuses on national statistics, but includes some data for individual States and regions and for Canada. The data were collected from industry trade associations and government agencies. They are intended for use by forest land managers, forest industries, trade associations, forestry schools, renewable resource organizations, individuals in the major timber producing and...

This literature review reports in-service moisture and temperature conditions of floor, wall, and roof members of wood-frame buildings and exposed wood decks and permanent wood foundations. A wide variation exists in reported wood moisture content, spanning a range from as low as 2% to well above 30%. Relevant studies are summarized, and measured values of wood moisture content and temperature are tabulated. Trends are discussed that relate moisture conditions to climate and season, moisture sources and transport mechanisms, and building design and construction.