Treesearch

Mature longleaf pine (Pinus palustris Mill.) trees were harvested to compare wood property data for opposing bark-to-pith wood strips representing the northern and southern cardinal (or compass) directions. For each of the ten 70-yr-old trees used in the study, wood property data were compared at breast height (BH) and three relative heights: one-quarter height (1Q), midheight (MID), and three-quarter height (3Q). Scanning of the specimens by X-ray densitometry gave specific gravity (SG) profiles that were used to determine wood properties for comparison. No significant differences were...

Raffaelea lauricola is the causal agent of laurel wilt and a fungal symbiont of its vector, the redbay ambrosia beetle, Xyleborus glabratus. Beetle populations increase rapidly where redbays have died from laurel wilt. In a series of experiments using bolts from healthy and diseased trees, X. glabratus reproduced better in bolts from diseased redbay; ratio of beetles emerged to entrance holes (BE/EH ratio) ranged from 4.1 to 6.0 in diseased bolts versus 0.3 to 1.9 in healthy bolts. Emergence was greater from redbay bolts when their ends were treated with paraffin wax compared to untreated...

Background: Forest biodiversity is the foundation of many ecosystem services, and the effect of biodiversity on ecosystem functioning and processes (BEF) has been a central issue in biodiversity studies. Although many hypotheses have been developed to interpret global gradients of biodiversity, there has not been complete agreement on mechanisms controlling biodiversity patterns and distributions. Differences may be due to limited observation data and inconsistencies of spatial scales in analysis. Methods: In this study, we take advantage of USDA Forest Service forest inventory and...

In boreal forests and alpine treelines, it is debatable how the temperature sensitivity of tree-ring growth should vary with changes in climate over time and the extent to which seasonal stem increments are controlled by leaf physiology. We aim to test the hypothesis that, in cold-limited forests, maximizing stem growth rate around summer solstice is closely related to foliage turnover, which generally results in high sensitivity of stem growth and less sensitivity of nitrogen-use efficiency (NUE) to early-season temperatures. Our analysis was based on repeat-census observations of stem...

This resource update provides an overview of forest resources in North Carolina based on an inventory conducted by the U.S. Forest Service, Forest Inventory and Analysis (FIA) program at the Southern Research Station in cooperation with the North Carolina Forest Service. Data estimates are based on field data collected using the FIA annualized sample design and are updated yearly

By the late 1920s, most of the big southern pine lumber operations had cut out their virgin timber, or were on the cusp of doing so. Only a few had started dabbling with sustainable forestry—“perpetual forestry,” as some called it. This USDA Forest Service image, taken in January 1926 by Wilbur R. Mattoon, captures the essence of the limited southern pine silvicultural options available at that time.

Much like flowering plants set the stage for an explosion of herbivore and pollinator diversity, the origin of dead wood in early Devonian forests (~400 mya) was followed by an incredible diversification of life, giving rise to some of the most successful morphological adaptations and symbioses on Earth. Approximately one third of all forest insect species worldwide depend directly or indirectly on dying or dead wood (i.e., saproxylic), with major functional groups including wood feeders, fungus feeders, saprophages, and predators. Although beetles and flies dominate saproxylic insect...

Consisting of about 1000 species globally, beetles of the family Passalidae feed on decomposing wood in tropical and subtropical forests throughout the world. Passalids live in subsocial family groups within their galleries, characterized by overlapping generations, cooperative brood care, and a complex communi- cation system involving stridulations. In what has been referred to as an “external rumen,” larval passalids feed on the microbe-rich frass and finely chewed wood paste produced by the wood feeding adults. Endosymbionts found within the guts of passalids include a variety of...

Diptera rivals Coleoptera as perhaps the most abundant and diverse order of saproxylic insects, with saproxylic habits known from at least 75 (48%) of the 157 fly families recognized globally. Some fly families are mostly if not entirely saproxylic including Aulacigastridae, Axymyiidae, Canthyloscelidae, Clusiidae, Pachyneuridae, Pantophthalmidae, Periscelididae, Xylomyidae, and Xylophagidae. Saproxylic flies are common inhabitants of virtually all moist to wet microhabitats including sap flows, under bark, in rotting wood, tree hollows, and fungal fruiting bodies. Most species are saprophagous...

The small southern pine engraver, Ips avulsus Eichhoff (Coleoptera: Scolytidae), is one member of a guild of southern pine bark beetles that causes millions of dollars of losses to southern U.S. pine forests annually. Our objective was to determine the impact of a commercial preparation of the entomopathogenic fungus Beauveria bassiana (Balsamo-Crivelli) Vuillemin (Ascomycota: Hypocreales) in protecting pine host plant tissue from colonization and damage by I. avulsus and on the B. bassiana–induced mortality of I. avulsus adults during the first 2 wk of host attack. The field trials were...