Treesearch

With relative humidity and temperature data from the National Oceanic and Atmospheric Administration, the average equilibrium moisture content for each month of the year was calculated for 262 locations in the United States and 122 locations outside the United States. As an aid for storage of kiln-dried lumber, a graph is presented for determining the reduction in equilibrium moisture content that results from heating air in an enclosed storage space above the temperature of the outside air.

This report describes strategies for using the Financial Evaluation of Ecosystem Management Activities (FEEMA) software. This program was developed as a tool for assessing the financial viability of management activities for removing small trees for manufacture into wood products. Combinations of tree stands, management activities, and contractual requirements can be ranked along a continuum from actions that are unlikely to pay for themselves under any economic conditions to those that are likely to cover their implementation costs. The program can be used early in the planning process to...

Dry-kiln schedules have been developed for many hardwood species, but many more, especially tropical species, do not have a recommended schedule. The study reported herein investigated the possibility of estimating kiln schedules using specific gravity (SG). Using known schedules and SG data of 268 hardwood species, a classification approach and linear regression analysis were applied and compared to establish the relationships between kiln schedule code numbers and SG. In general, schedule predictions matched reasonably well with recommended schedules, but for some species, the differences...

Ring-shank nails are used extensively in post-frame construction due to their superior performance, yet surprisingly little testing has been done on nail sizes above 12d Experience in the post-frame industry suggests that published allowable design values for ring-shank nails may be overly conservative and need revision. The goal of the research reported herein was to characterize the withdrawal strength of ring-shank nails embedded in Southern Pine lumber. Three sizes of galvanized and ungalvanized (bright) ring-shank nails from two manufacturers were studied. Ring-shank nails had...

In the United States, log grading procedures use visual assessment of defects, in relation to the log scaling diameter, to estimate the yield of lumber that maybe expected from the log. This procedure was satisfactory when structural grades were based only on defect size and location. In recent years, however, structural products have increasingly been graded using a combination of visual estimation of defects, coupled with nondestructive evaluation of other parameters, to obtain a more precise estimate of product properties. Today, the most commonly used nondestructive evaluation parameter...

The objective of this project was to compare the different methods for the quantification of micro stickies. The hydrophobic materials investigated in this project for the collection of micro stickies were Microfoam* (polypropylene packing material), low density polyethylene film (LDPE), high density polyethylene (HDPE; a flat piece from a square plastic bottle), paper machine wire (polyester), and Tyvek* (Federal Express envelope). A stainless steel frame, built to hold the collecting material, was used to insert each material into the pulp under controlled conditions. Collected micro...

Antagonistic characteristics of a commercial biofungicide, Trichoderma (Gliocladiurn) virens (GL-21, W. R. Grace and Co., CT), were evaluated against three white-rot fungi, Trametes versicolor, Phlebia brevispora, Irpex lacteus, and three brown-rot fungi, Postia placenta, Neolentinus lepideus, and Gloeophyllum trabeum. In dual cultures of T. virens and wood decay fungi, T, virens rapidly overgrew and killed the decay fungi. Pretreatment of Southern Pine and maple blocks with T. virens prevented weight loss by all decay fungi in the soil-block tests. T. virens colonized blocks, treated with...

Kraft and thermomechanical (TMP) pulps were prepared and evaluated from lodgepole pine and mixed Douglas-fir/western larch sawmill residue chips; lodgepole pine, Douglas-fir, and western larch submerchantable logs; and lodgepole pine, Douglas-fir, and western larch small trees and tops. Kraft pulp from small trees and tops was identical to that from submerchantable logs, except for Douglas-fir submerchantable logs. Lodgepole pine showed higher yield than western larch at the same target kappa levels. The handsheet properties of western larch from different raw material sources were the...

The goal of this research was to develop nondestructive evaluation (NDE) technology to enhance mechanical stress rating of lumber. An ultrasonic NDE technique was developed that is sensitive to grain angle and edge knots in lumber - two primary determinants of lumber strength. The presence of edge knots increased the acoustic wave travel time and selectively attenuated the higher frequency ultrasonic energy. NDE measurements and tension tests were performed on 200 pieces of nominal 50 × 150 mm Southern Pine lumber. Statistical models were developed from localized stress wave indices to...

In studies on wood strength, researchers sometimes replace experimental unit allocation via random sampling with allocation via sorts based on nondestructive measurements of strength predictors such as modulus of elasticity and specific gravity. This report documents TT, a computer program that implements recently published methods to increase the sensitivity of such bpredictor sortc experiments. The report consists of annotated keyboard sessions and computer output from runs of TT.