Treesearch

Cover cropping, where a crop is planted but not harvested, is an important practice for maintaining soil health because it keeps like roots in the soil for as much of the year as possible. In colder temperate regions, cold-tolerant covers are available, but not widely used. We hypothesized that a cover crop that could be harvested as a valuable vegetable might increase uptake of cover cropping. We used field, high tunnel, and laboratory experiments to explore the cold tolerance and agronomic viability of overwintering peas in Vermont in the Northeastern United States. We found no difference...

The long-term sustainability of white oak (Quercus alba L.), an ecologically and economically important species in the eastern United States (US), appears to be threatened by demographic constraints. Earlier research has highlighted widespread bottlenecks in the process of recruiting white oak saplings (2.5 cm - 12.7 cm dbh) into small trees (dbh ≥ 12.7 cm). Thus, the fate of white oak saplings is a key component in understanding whether shortfalls in larger size classes are due to an onset of challenges when white oaks reach the small tree size or are an artifact of unsustainable sapling...

The emerald ash borer is an invasive pest causing widespread mortality of ash trees (Fraxinus spp.) across the USA. Broad-scale models can help identify management strategies to maintain lowland ash ecosystems. Simulating lowland forest dynamics in landscape models has been problematic because lowland hydrology is extremely complex, making most hydrology algorithms intractable at the landscape scale. A succession extension (PnET-Succession) of the LANDIS-II forest landscape model was recently updated to include simple algorithms to approximate lowland hydrology, but estimating parameters...

This chapter provides an overview and comparisons of the precipitation intensity–duration–frequency (PIDF) and flood (FFRQ) and low-flow (LFRQ) frequencies for return intervals of 25 years or more at ten relatively undisturbed reference watersheds in the US Forest Service Experimental Forest (EF) network. We demonstrate potential effects of recent climate change on the PIDFs, FFRQ and LFRQ developed with high-resolution temporal data at these ten sites with widely contrasting hydrogeological, topographical, climatic and ecological characteristics. Similarly, we evaluate the on-site-based...

Silvicultural practices in forestry include activities such as site preparation, tree planting, thinning, and tree harvesting. Sometimes single trees are removed while in other cases large tracts of forest are clearcut. Logging activities bring about many environmental changes in light, temperature, soil moisture and vegetation structure, and thus can influence local plant and animal communities. Ground beetles (Carabidae) are good bioindicators of environmental change because they are (1) highly sensitive to habitat alterations, (2) diverse, (3) abundant, and (4) well known taxonomically....

Primary dispersers of seeds and spores play critical roles in structuring the distributions of species, yet the role of predators as secondary dispersers remains largely unknown. This is especially true of mycorrhizal fungi, which often rely on small mammals to consume and disperse spores. We investigated how predator size, diet, and movement influence secondary spore dispersal in a terrestrial carnivore community by quantifying spore loads in scats (dispersal quantity) and integrating movement rates with gut passage time to determine dispersal distance (dispersal quality). Spores in...

Forest managers recognize that proactive management strategies, such as forest assisted migration (FAM) of tree species, intended to accelerate the pace of forest adaptation, may be necessary to maintain resilient forests and combat the stressors of climate change. However, the impact of interactions between climate change and ungulate browsers of trees, both of which have profound effects on the landscape, on the success of FAM efforts is unknown. We used a forest landscape model (LANDIS‐II) to simulate assisted migration and browsing by ungulate (white‐tailed deer [ Odocoileus virginianus...

Conifers have been widely planted to stabilize soils and promote site recovery on former hardwood sites that were cleared for agriculture. Decades of confer occupancy may have lasting effects on nutrient availability, organic matter cycling, soil acidity, and soil buffering capacity. In many areas of eastern North America, conifer plantings consisted of non-native Pinus species planted on abandoned agricultural land that was once mesophytic hardwood forest. To investigate the long-term effect of Pinus occupancy on former hardwood soils, we compared the soil chemistry of P. echinata and P....

We studied the effects of trapping intensity and lure combinations on Scolytinae (Coleoptera: Curculionidae) collections, using funnel traps at 16 sites including forests and Christmas tree farms near Erie, Pennsylvania and Toledo, Ohio, United States of America. In 2002, using 16 or 64 traps per site, all baited with α-pinene + ethanol, we collected 146 627 specimens from 40 species altogether. With 16 traps, 15–24 scolytine species were collected per site, whereas 28–31 species were collected with 64 traps. On average, 55% of all scolytine species collected with 16 traps were collected...

Background: Fires can alter soil properties via downward heat transfer. Numerous studies have examined effects of wildfires and prescribed burns on soils, yet knowledge of the soil temperatures and durations reached is limited. This can lead to erroneous assumptions regarding fire impacts, especially when laboratory heating results are extrapolated to field conditions.Aims and methods: We compiled new and published data on maximum temperatures and heating durations for mineral soils during wildfires and prescribed burns in forests, shrublands and grasslands around the globe, and compared...