Treesearch

Previous studies have proven that short-day treatment is an effective means to regulate shoot growth and abiotic stress resistance in conifers. However, the effects on Chinese pine (Pinus tabuliformis) seedlings are less well known. In this study, short-day treatments were applied to container-grown Chinese pine seedlings by artificially reducing day length to 8 or 10 h for 3 weeks. Growth and physiological responses of the seedlings were evaluated. In addition, proteome analysis using two-dimensional electrophoresis in combination with MALDI-TOF/TOF MS analysis was performed on needles of...

This article reviews current data on forest wetlands and their economic contributions in the South, ranging from Texas to Virginia. Based on USDA Forest Service Forest Inventory and Analysis (FIA) data, the wetland category comprised 17.7% of timber land area on all private and public lands in the South. This included 4.25 million ha of hydric sites; 0.77 million ha mesic wet; 9.55 million ha mesic, with only seasonal access; for a total of 14.57 million ha. The Natural Resource Inventory (NRI) for 2012 on private lands estimated that there were 14.71 million ha forested wetlands, which...

Historical forests in the Southeastern Mixed Forest province of the United States have been less researched than other regions using historical tree surveys. We used 81,000 tree records from surveys during the 1800s to quantify composition of this ecological province. Upland oaks and pines comprised about 75% of all trees, with relatively equal composition. Oak composition may have comprised ≥ 45% to the northern and eastern sides of the province. Hickories were about 10% of composition and a few species were present at 1% to 2% composition. Currently, pine has increased to 49% composition;...

We examined the contribution of large trees to forest density, richness and biomass using a global network of 48 large (from 2 to 60 ha) forest plots representing 5,601,473 stems across 9,298 species and 210 plant families. This contribution was assessed using three metrics: the largest 1% of trees ≥ 1 cm diameter at breast height (DBH), all trees ≥ 60 cm DBH, and those rank-ordered largest trees that cumulatively comprise 50% of forest biomass.

High-quality information is needed for conservation and management of aquatic resources on lands administered by the U.S. Forest Service (USFS). Information is ultimately derived from data, so the USFS maintains a series of databases that are used to describe the status and trends of aquatic habitats and biota. The databases are spatially explicit and are crowd-sourced, meaning that distributed networks of professionals and technicians operating throughout the National Forest System collect stream and biological measurements, which are stored in central repositories. How those databases...

The Rocky Mountain Research Station recently published a general technical report addressing climate change vulnerability in the Rocky Mountain Region. This report, entitled Climate Change Vulnerability Assessment of Aquatic and Terrestrial Ecosystems in the US Forest Service Rocky Mountain Region, focuses on six ecosystems. Scientists evaluated each ecosystem based on several factors, including their current extent, exposure to climate change, sensitivity and adaptability to climate change, the ability of the ecosystem to shift geographically, and non-climate stressors such as recreational...

We studied blue-stain fungi (Ophiostomataceae: Ophiostomatales) of mountain pine beetle in declining epidemic populations affecting three pine species in Colorado. Using morphological and molecular characterizations, we determined the presence of the mutualist L. longiclavatum in the southern Rocky Mountains of Colorado, where it was as common as the warm temperature adapted O. montium within the insect’s specialized maxillary mycangium. The species was more prevalent than its “sibling species” G. clavigera which is the the common mycangial mutualist documented in USA populations. Findings...

The mite and fungal biota associated with the mountain pine beetle (MPB) (Dendroctonus ponderosae Hopk.) may not be stable throughout an irruptive event. In congeneric beetles, variations in the frequency of their associated organisms affect population trends and similar effects may occur in MPB.We studied fungi and mite trends in a declining irruptive MPB population as it attacked three different pine hosts in the Colorado Front Range. During the study, we found two new associates including one biologically relevant mite and one beneficial blue-stain fungus. Fungi hyperphoretic on mites...

The La Sal daisy, Erigeron mancus, is endemic to treeline ecotone and alpine meadow habitats of the La Sal Mountains in Utah, an insular, laccolithic mountain range on the Colorado Plateau in southeastern Utah. From 2009 to 2011 we established elevational transects through upper spruce-fir forest, treeline ecotone, and alpine meadow habitats on Laurel Ridge in the Middle Mountain group of the La Sal Mountains to measure (1) periodic changes in E. mancus population density, (2) changes in the elevation of the E. mancus population centroid, (3) changes in patch size occupied by E. mancus,...

Environmental DNA (eDNA) sampling - the detection of genetic material in the environment to infer species presence - has rapidly grown as a tool for sampling aquatic animal communities. A potentially powerful feature of environmental sampling is that all taxa within the habitat shed DNA and so may be detectable, creating opportunity for whole‐community assessments. However, animal DNA in the environment tends to be comparatively rare, making it necessary to enrich for genetic targets from focal taxa prior to sequencing. Current metabarcoding approaches for enrichment rely on bulk amplificat...