Treesearch

Weed infestations cause an economic loss of $13 billion per year even though $9.5 billion per year is spent on weed control measures. In addition to these economic costs, weeds are replacing native species, altering native plant and animal communities, affecting ecosystem health and function, threatening biodiversity and Threatened, Endangered, and Sensitive (TES) species, altering fire behavior and fire regimes, and reducing wildland productivity. This paper discusses (1) where weeds are found, (2) what promotes weed invasions, and (3) how to incorporate weed management into fuel treatment...

Managers face a difficult task in predicting the effects of fuels treatments on wildlife populations, mostly because information on how animals respond to fuels treatments is scarce or does not exist. This paper discusses key considerations-aspects of an animal's ecology and available information-that, despite the scarcity of information, may make predictions of effects possible.Other publications in this series

The geographic focus of the "Fuels Planning: Science Synthesis and Integration" project #known as the Fuels Synthesis Project# is on the dry forests of the Western United States. Target audiences include fuels management specialists, resource specialists, National Environmental Policy Act #NEPA# planning team leaders, line officers in the USDA Forest Service and the Department of the Interior; community leaders; and educators

Organic matter (OM) decomposition is an important variable in forest productivity and determining the potential of forest soils to sequester atmospheric CO2 (Grigal and Vance 2000; Kimble et al. 2003). Studies using OM from a particular location gives site-specific decomposition information, but differences in OM type and quality make it difficult to compare results among soils and forest ecosystems. By using a “standard” OM in decomposition studies, OM quality is held constant, and decomposition is a function of soil abiotic (moisture, temperature, O2/CO2, redox potential, pH, N, P, etc),...

A series of common garden studies of 336 populations representing Picea engelmannii, P. pungens, P. glauca, P. mexicana, and P. chihuahuana provided as many as 13 growth and morphologic characters pertinent to biosystematics and genecology. Canonical discriminant analyses discretely segregated populations of P. pungens and P. chihuahuana while positioning P. engelmannii populations along a continuum anchored by Southwestern United States populations at one extreme and those classified as hybrids of P. engelmannii with P. glauca on the other. A population of P. mexicana was closely aligned...

The fixed number of trees sample design proposed by Jonsson and others (1992) may be dangerous in applications if a probabilistic framework of sampling is desired. The procedure can be seriously biased. Examples are given here.Publication Web Site:https://www.fs.usda.gov/rm/pubs/rmrs_rn017.html

Soil compaction is an important indicator of soil quality, yet few practical methods are available to quantitatively measure this variable. Although an assessment of the areal extent of soil compaction is included as part of the soil indicator portion of the Forest Inventory & Analysis (FIA) program, no quantitative measurement of the degree of soil compaction is made. We tested a small, lightweight pocket penetrometer that measures soil compression strength as a simple, quantitative measure of the degree of compaction of mineral soils under forested conditions. Soil compression strengths...

The effects of thinning Emory oak (Quercus emoryi) coppice on transpiration have been estimated by the heat-pulse velocity (HPV) method. Rootstocks of trees harvested for fuelwood were thinned to one, two, or three dominant stump-sprouts or left as unthinned controls. Differences in transpiration rates of the thinned coppice were found for each treatment and the control. Earlier research has also shown that thinning of Emory oak stumpsprouts influences the growth and volume of the residual coppice and its value for wildlife habitats. Therefore, a decision matrix is presented to help in the...

Interactions between fungi and woody roots may be critical factors that influence diverse forest ecosystems processes, such as wood decay (nutrient recycling); root diseases and their biological control; and endophytic, epiphytic, and mycorrhizal symbioses. However, few studies have characterized the diversity and the spatial and temporal distribution of woody root-associated fungi in forest ecosystems. Molecular genetic techniques that facilitate fungal identification are now available to help investigate complex and dynamic interactions of these fungi.Publications Web Site:https://www.fs....

The objective of this study was to simultaneously evaluate the impact of leafy spurge (Euphorbia esula L.) on plant species richness within and among a wide variety of vegetation types typical of the region. The study was conducted in Theodore Roosevelt National Park in southwestern North Dakota where 11 plant associations were identified as being particularly susceptible to invasion by leafy spurge. Representative infested and non-infested stands of the 11 associations were sampled using the protocol described by the National Vegetation Classification System. To evaluate the effects of...