Treesearch

Models that quantify the probability of stump sprouting P(s) and sprout characteristics for predominant tree species in the southern Appalachian Mountains, USA are lacking. In this study, 375 plots (0.01 ha) were installed across five stands in eastern Tennessee and western North Carolina. Trees C3.8 cm diameter at 1.37 m above groundline (dbh) were tagged, and dbh and species recorded. Stands were regenerated using a two-aged silvicultural system (residual basal area (BA) \6.3 m2 ha-1 ). One growing season post-harvest, we recorded (1) sprouting (yes/no), (2) the number of sprouts per...

The mountain pine beetle-killed lodgepole pine (Pinus contorta) wood treated with iron (III) nitrate solution was used for the preparation of Fe-cored carbon nanomaterials (Fe-CNs) under various carbonization temperatures. The carbonization yield of Fe-treated sample (5% as Fe) was always 1–3% higher (after ash compensation) than that of the non-treated samples heated at the same condition.The lowest carbonization temperature required to produce Fe-CNs was 700° C. The carbon shell was composed of 30–40 well-aligned layers of graphitic carbon nanostructure.The iron captured by graphitic...

Previous research revealed that stress wave nondestructive testing techniques could be used to evaluate the tensile and flexural properties of wood-based composite materials. Regression models were developed that related stress wave transmission characteristics (velocity and attenuation) to modulus of elasticity and strength. The developed regression models accounted for over 94% of these materials’ observed elastic properties and for over 90% of their observed strength. The original models were developed using wood-based particle composite specimens. The study presented in this paper...

The use of a variety of stress wave transmission techniques for the in-service condition assessment of deteriorated wood is well documented. This paper summarizes results from an extensive study designed to examine the relationship between ultrasound transmission times and the deterioration of exposed wood. Two hundred seventy (270) southern pine lumber specimens were evaluated nondestructively using a through transmission ultrasound technique after field exposure for periods of up to fifty seven (57) months. Ultrasound transmission times increased with exposure time. Several statistical...

Spatially nonuniform runoif reduces the water qua1iry perfortnance of constant- width filter strips. A geographic inlormation system (Gls)-based tool was developed and tested that ernploys terrain analysis to account lor spatially nonuniform runoffand produce more ellbctive filter strip designs.The computer program,AgBufTerBuilder, runs with ATcGIS versions 10.0 and 10.1 (Esri,Redlands,California) and uses digital elevation models to identify detailed spatial patterns of overland runoff to field margins.The tool then sizes filter dimensions according to those patterns using bufTer area...

EXCERPT FROM: Natural Disturbances and Historic Range Variation 2015. Throughout the history of upland hardwood forests of the Central Hardwood Region, natural disturbances have been integral to shaping forest structure and composition, and essential in maintaining diverse biotic communities. In this chapter, we introduce the geographic scope and dynamic history of climate, natural disturbances, and human influence on central hardwood forests. We briefly introduce biotic and abiotic agents of disturbance to provide a foundation for the book and further discussion of whether and how...

EXCERPT FROM: Natural Disturbances and Historic Range Variation 2015
Multiple natural disturbance types historically created conditions thatwere suitable for many, but not all, disturbance-dependent wildlife species in the Central Hardwood Region (CHR). In addition, some wildlife species, such as beavers, passenger pigeons, elk, and bison, historically functioned as keystone species by creating or maintaining unique disturbed habitats that otherwise would be rare. For millennia, humans (Native Americans, and later European settlers) also created and maintained early successional...

EXCERPT FROM: Natural Disturbances and Historic Range Variation 2015. The southern pine beetle (SPB) is a major disturbance in pine forests throughout the range of southern yellow pines, and is a significant influence on forests throughout several Central Hardwood Region (CHR) ecoregions. At endemic levels, SPB colonizes individual stressed or lightning-struck trees, acting as a natural thinning agent. During outbreaks, tree mortality from SPB may impact CHR forests by indirectly converting stands to other species types, or changing the stand age and structure. Southern pine beetle can...