Treesearch

The depletion of root-available calcium in northern forests soils exposed to decades of increased acid deposition adversely affects forest health and productivity. Laboratory studies indicated the potential of wood-decay fungi to restore lost calcium to the rooting zone of trees. This study reports changes in concentrations of Ca, Mg, and K during decay of sapwood of spruce, maple, hemlock, and birch at two locations in northern New England, USA. Concentrations of exchangeable Ca, Mg, and Al in decayed wood residues after 10 and 12 years of ground contact were also compared. Significant...

Nitrogen (N) deposition affects forest biogeochemical cycles worldwide, often contributing to N saturation. Using long-term (>30-year) records of stream nitrate (NO3-) concentrations at Fernow Experimental Forest (West Virginia, USA), we classified four watersheds into N saturation stages ranging from Stage 0 (N-limited) to Stage 3 (N-saturated). We quantified NO3- contributions from atmospheric and microbial sources using δ15N, δ18O, and Δ17O of NO3- and characterized the concentrations and isotopes of NO3- in precipitation. Despite receiving identical atmospheric inputs, the proportions...

Prescribed fire and timber harvest are anthropogenic disturbances that modify resource availability and ecosystem structure, and can affect wildlife both directly and indirectly. Terrestrial salamanders are effective indicators of forest health due to their high abundance and sensitivity to microclimatic conditions. Given their ecological importance, it is critical to understand how forest salamanders respond to management-related disturbances. We predicted that timber harvest and prescribed fire would decrease salamander abundance and availability, and increase salamander cover object...

There is interest in restoring shortleaf pine (Pinus echinata) in pine–oak woodlands where it once was abundant. Because of its shade intolerance and slow initial growth rate, shortleaf pine restoration has remained a challenge because competition from hardwoods exhibits greater initial growth following canopy removal but greater shade tolerance with canopy retention. The study objective was to examine the survival and growth of underplanted shortleaf pine seedlings relative to competing hardwoods as a function of initial seedling size, overstory density, and understory competition. In the...

With increasing public demand for more intensive biomass utilization from forests, the concerns over adverse impacts on productivity by nutrient depletion are increasing. We remeasured the 1974 site of the Forest Residues Utilization Research and Development in northwestern Montana to investigate long-term impacts of intensive biomass utilization on aspects of site productivity. The historical experiment was implemented in a western larch (Larix occidentalis Nutt.) forest at three biomass utilization levels (high, medium, and low) combined with prescribed post-harvest burning treatments...

Commercial lumber production in the Lake States, which began in the early 1800s with eastern white pine (Pinus strobus L.), shifted to hardwoods in the late 1800s (Whitney 1994). Much of the hardwood forest was rapidly cut over; as a consequence, mill capacity exceeded available stumpage by the 1920s (Eyre and Zillgitt 1953). The forest industry recognized the need for sustained-yield practices, but faced numerous financial and managerial problems and most landowners continued to liquidate their timber.

White-tailed deer (Odocoileus virginianus) are common in forests and farmlands throughout the United States and Canada. While their propensity for eating gardens and ornamental plants is well-known to frustrated homeowners, few outside the wildlife and forestry professions are aware of the profound effects deer have on forest understory composition and growth. Even when populations are not exceedingly high, deer have a controlling effect on forest vegetation in many regions, including the northeastern and north central U.S. and southern Canada where their range overlaps with that of the...

Biomass harvesting extracts an increased amount of organic matter from forest ecosystems over conventional harvesting. Since organic matter plays a critical role in forest productivity, concerns of potential negative long-term impacts of biomass harvesting on forest productivity (i.e., changing nutrient/water cycling, aggravating soil properties, and compaction) have emerged. There is abundant prediction of long-term impacts of intensive biomass removal on forest productivity. However, the empirical knowledge and comprehensive understanding, especially on western forests, are limited thus...

We investigated potential source areas of dissolved organic carbon (DOC) in headwater streams by examining DOC concentrations in lysimeter, shallow well, and stream water samples from a reference catchment at the Hubbard Brook Experimental Forest. These observations were then compared to high-frequency temporal variations in fluorescent dissolved organic matter (FDOM) at the catchment outlet and the predicted spatial extent of shallow groundwater in soils throughout the catchment. While near-stream soils are generally considered a DOC source in forested catchments, DOC concentrations in...

The Fernow Experimental Forest (herein called the Fernow) in Tucker County, WV, was set aside in 1934 for “experimental and demonstration purposes under the direction of the Appalachian Forest Experiment Station” of the US Forest Service. Named after a famous German forester, Bernhard Fernow, the Fernow was initially developed with considerable assistance from the Civilian Conservation Corps. Shut down temporarily during World War II, the Fernow was reopened in 1948 as an outdoor laboratory and classroom with the purpose of conducting research that would be useful to the forest landowners...