Treesearch

This study used ring width correlations to examine the effects of tree-growth suppression on within-tree local wood density and tracheid anatomical properties. A wood core sample was taken from a 70-yr-old Douglas-fir that grew under various degrees of suppression in a natural forest setting. SilviScan and an imaging technique were used to obtain wood density and tracheid cross-section dimensions. The results indicated that wood and tracheid properties correlate to annual-ring width very well. The results also reveal that growth suppression may increase the uniformity of wood density and...

Dusting of termites in situ has been used as a control measure for decades; however environmental awareness of the toxicity of certain compounds now limits their use (eg arsenical dusts). Our laboratory is in the process of suppressing an isolated colony of Reticulitermes flavipes (Kollar) from a small village of 250 homes in mid-central Wisconsin (Endeavor, WI). Initial treatment of the colony involved the use of 200 Microgen bait cartridges containing 0.25% diflubenzuron. The presence of many living termites occupying bait stations throughout the season prompted the addition of various...

The degradation of lignin by filamentous fungi is a major route for the recycling of photosynthetically fixed carbon, and the oxidative mechanisms employed have potential biotechnological applications. The lignin peroxidases (LiPs), manganese peroxidases (MnPs), and closely related enzymes of white rot basidiomycetes are likely contributors to fungal ligninolysis. Many of them cleave lignin model compounds to give products consistent with those found in residual white-rotted lignin, and at least some depolymerize synthetic lignins. However, none has yet been shown to delignify intact...

Biodegradation by brown-rot fungi is quantitatively one of the most important fates of lignocellulose in nature. It has long been thought that these basidiomycetes do not degrade lignin significantly, and that their activities on this abundant aromatic biopolymer are limited to minor oxidative modifications. Here we have applied a new technique for the complete solubilization of lignocellulose to show, by one-bond 1H-13C correlation nuclear magnetic resonance spectroscopy, that brown rot of spruce wood by Gloeophyllum trabeum resulted in a marked, non-selective depletion of all intermonomer...

A training needs assessment of the primary forest products industry was conducted for 33 eastern states. his publication presents in detail the statistical analysis of the study. Of the 2,570 lumber manufacturing companies, consisting of firms with more than six employees for the U.S. Department of Labor Standard Industrial Classification Code 2421, the response rate to the survey was 18.1%. The study found that over the next 5 years, 36% of the current skilled positions are projected to be replaced. Based on the number of new key employees that will be needed to replace current employees,...

This study evaluated a series of single-layer, randomly oriented strandboard panels made with one resin type, a single resin loading level, and four fire-retardant-treatment levels. The fire retardant (FR) evaluated was a pH-buffered combination of boric acid and organic phosphate. Siberian larch strands were separated into five batches. One batch of strands served as the untreated control group and was not treated with water or FR; the four other batches were individually treated using a vacuum–pressure–soak process of the strands in water or three progressively higher concentrations of...

Using sustainable building materials is gaining a significant presence in the United States therefore proving sustainability claims are becoming increasingly more important. Certifying wood products as green building materials is vital for the long-term productivity of the wood building industry and for forest management. This study examined hardwood lumber manufacturing using Life-Cycle Inventory methodology. Material flow and energy type and use were identified for hardwood sawmills in the northeastern United States. Energy consumption of 608 MJ of electricity and 5,800 MJ of thermal...