Treesearch

Moisture availability is a key factor that influences white oak (Quercus alba L.) growth and wood production. In unglaciated eastern North America, available soil moisture varies greatly along topographic and edaphic gradients. This study was aimed at determining the effects of soil moisture variability and macroclimate on white oak growth in mixed-oak forests of southern Ohio. Using accurately dated and measured tree rings, we analyzed 119 white oaks growing across an integrated moisture index (IMI), a computer-generated GIS model that simultaneously combines topographic and edaphic...

In many industrialized regions of the world, atmospherically deposited sulfur derived from industrial, nonpoint air pollution sources reduces stream water quality and results in acidic conditions that threaten aquatic resources. Accurate maps of predicted stream water acidity are an essential aid to managers who must identify acid-sensitive streams, potentially affected biota, and create resource protection strategies. In this study, we developed correlative models to predict the acid neutralizing capacity (ANC) of streams across the southern Appalachian Mountain region, USA. Models were...

Since acid deposition increases the rate of deterioration of unpainted wood, it can also affect the performance of paint applied to this weathered wood. In tests conducted near Madison, Wisconsin, smooth-planed wood was allowed to weather before painting. Exposure for as little as 2 weeks shortened the service life of the subsequently applied paint. The paint bond was weak and the paint eventually peeled. Acid concentration in rain near Madison tends to be much lower than that found in many other areas of the United States. High acid concentration would tend to produce more surface...

Iron stain, an unsightly blue–black or gray discoloration, can occur on nearly all woods. Oak, redwood, cypress, and cedar are particularly prone to iron stain because these woods contain large amounts of tannin-like extractives. The discoloration is caused by a chemical reaction between extractives in the wood and iron in steel products, such as nails, screws, and other fasteners and appendages. This often occurs the first morning after rain or dew, when water enables the extractives and iron to meet and react. For hundreds of years, ink was made by mixing tannin and iron in solution,...

Since the mid-1980s, a condition called “mill glaze” (also called planer’s glaze) has sometimes been blamed for the failure of a coating on smooth flat-grained siding and some other wood products. The exact cause of this problem has been a subject of controversy. Many people believe that the coating fails as a result of the planing and/or drying processes. They speculate that the milling or planing process overheats the wood and brings more water-soluble extractives to the surface, creating a hard varnishlike glaze. They attribute overheating to dull planer blades.

The hemlock woolly adelgid, Adelges tsugae Annand, is a serious, non-native pest of hemlock in eastern North America. Laricobius osakensis Montgomery and Shiyake was identified as a key predator in Japan, where A. tsugae is native. Performance of adult and immature stages of L. osakensis was evaluated in sleeve cages on adelgid infested Tsuga canadensis (L.) Carriere in plant hardiness zones 5b and 6b in the mountains of southwestern Virginia, USA. Adults fed on the adelgid and laid eggs during all biweekly sample periods from December 2010 to May 2011, including winter when the temperature...

The main objective of this study is to evaluate the effect the oxalic acid (OA) and steam pretreatment on the primary properties of rice straw medium-density fiberboard (MDF). The results show the IB strength increased about 9.6% and 13.4% for steam-treated MDF (PC) and OA-treated MDF compared with raw control panels, while OA pretreatment has a slight negative effect on the bending properties of MDF. Generally, the steam-treated and OA-treated panels exhibit a slightly improved dimensional stability, but the difference is not significant compared with raw control panels. The thermo-mechani...

The Coronado National Forest is an administrative component of the National Forest System. It administers 1,783,639 acres of National Forest System lands. National forests across the United States were established to provide natural resource-based goods and services to American citizens, and to protect timber and watershed resources. Management of national forests is jointly based on the principles of conservation and multiple use. The Coronado National Forest contributes a wide array of goods and services to its visitors and communities.

Interactions among site conditions, disturbance events, and climate determine the patterns of forest species recruitment and mortality across landscapes. Forests of the American Southwest have undergone significant changes over a century of altered disturbance regimes, human land uses, and changing environmental conditions. Along steep vertical gradients such as those of southwestern Madrean Sky Island systems, where mountains rising out of the Sonoran Desert host biomes representing a latitudinal transect from Mexico to Canada, forests are especially vulnerable to changing dynamics of...

The U.S. Department of Agriculture, Forest Service, Coronado National Forest prepared this programmatic environmental impact statement to disclose the potential effects of a proposed action to revise the "Coronado National Forest Land and Resource Management Plan" (1986, as amended). The Coronado comprises 1,783,639 acres, most of which are located in southeastern Arizona, and 70,729 acres of which are in southwestern New Mexico.This document reports the results of an effects analysis of management direction in a no action alternative (i.e., the existing forest plan); the proposed action...