Treesearch

Computer models used to predict forest and fuels dynamics and wildfire behavior inform decisionmaking in contexts such as postdisturbance management. It is imperative to understand possible uncertainty in model predictions. We evaluated sensitivity of the Fire and Fuels Extension to the Forest Vegetation Simulator predictions to parameters that determine dynamics of standing dead trees (snags) and surface woody fuels. Predicted peak coarse and fine woody fuels were not sensitive to the decomposition rate of snags but were sensitive to decomposition rate of surface fuels regardless of...

Despite statements that it can mitigate financial risk through farm diversification, alley cropping in the United States Southeast has not been comprehensively modeled to estimate potential financial returns and risks. We used a Monte Carlo method to model stochastic financial returns to monocropping agriculture, loblolly pine plantation, and loblolly pine alley cropping in North Carolina, USA, plotting the results from 25,000 iterations to understand financial risk. Under certain scenarios and assumptions, alley cropping did have financial returns comparable to, or potentially higher than...

Concerns about food sovereignty in western nations have increased in recent years, as incidents of food-bornepathogens are highlighted in the popular press, and calls for locally-sourced food have increased. Wild foodforaging has emerged as a response by some segments of the population under the twin rubrics of food sovereigntyand food justice. However, virtually all studies looking at these activities focus outside of the U.S. Southand contain little information on African American involvement. We investigate both perceptions and participationin urban foraging by African Americans in...

In sagebrush ecosystems, pinyon and juniper tree expansion reduces water available to perennial shrubs and herbs. We measured soil water matric potential and temperatures at 13-30 and 50-65 cm soil depths in untreated and treated plots across a range of environmental conditions. We sought to determine the effects of tree expansion, tree reduction treatments, and expansion phase at time of treatment over 12-13 yr post-treatment. Because the effects of tree reduction on vegetation can vary with the soil temperature/ moisture regime, we also analyzed differences in soil climate variables...

Timely and accurate knowledge about the geospatial distribution of crops at regional to continental scales is crucial for forecasting crop production and estimating crop water use. The United States (US) is one of the leading food-producing countries, but lacks a nationwide high resolution crop-specific land cover map available publicly during the current growing season. The goal of this study was to map crops across the Continental US (CONUS) before the harvest, and to estimate the earliest date of classification by which crops can be mapped with sufficient accuracy (90% of full-season...

Southern pine beetle (Dendroctonus frontalis Zimmermann) and black turpentine beetle (Dendroctonus terebrans Olivier) are two sympatric bark beetle pests of the southeastern United States of America that adversely affect pine (Pinus spp.) health. Successful host tree colonization and reproduction is dependent on a chemical communication system that includes compounds produced by both the beetles and their host trees. To better understand the role of host volatiles in the ecology of these species, we (1) used coupled gas chromatography-electroantennographic detection (GC-EAD) to analyze...

Environmental DNA (eDNA) sampling can infer whether a species is present without the need to physically observe that species. DNA in cells sloughed off from organisms persists in the environment, where it can be collected as a water sample, extracted, and analyzed for any species of interest. Aspects of sample collection may vary depending on the type of water body (pond, lake, river, stream) and area sampled (surface water, very deep lake water, mucky pond water). Study design (where and when samples are collected) can also vary based on research questions. Depending on a biologist’s...

Invasive plants have the potential to affect decomposition both directly, by introducing novel substrates that may differ from native species in key structural or chemical properties, and indirectly through changes to soil properties and microbial communities. The relative importance of these two mechanisms is unclear, especially with regard to wood decomposition. To explore these questions, we used a novel method to rapidly assess the wood decay rates of 11 native and 11 invasive non-native angiosperm species. The study was repeated at three pairs of sites, each consisting of an invaded...