Treesearch

Forest ecosystem processes depend on local interactions that are modified by the spatial pattern of trees and resources. Effects of resource supplies on processes such as regeneration are increasingly well understood, yet we have few tools to compare resource heterogeneity among forests that differ in structural complexity. We used a neighborhood approach to examine understory light and nutrient availability in a well-replicated and largescale variable-retention harvesting experiment in a red pine forest in Minnesota, USA. The experiment included an unharvested control and three harvesting...

Understanding the behavioral basis of dispersal and colonization is critical in biological control systems, where success of a natural enemy depends in part on its ability to find and move to new host patches. We studied behavior of the specialist weevil Rhinoncomimus latipes Korotyaev, a biological control agent of mile-a-minute weed, Persicaria perfoliata (L.) H. Gross, by releasing weevils at the forest edge and monitoring their colonization of potted host plants arrayed along the edge, out into the open field, and into the forest. Both distance from the release cage and habitat where...

In the United States, 35% of the forestland is owned by family forest owners with approximately 0.2% of this land reported to be enrolled in a forest certification system. The current study was conducted to provide insights into factors influencing family forest owners’ decisions to certify their lands. The bivariate probit model with sample selection results suggests that receiving professional advice regarding the forestlands and having a written management or stewardship plan had the highest positive marginal effects on awareness of certification programs and participation in these...

This edition of Forest Nursery Pests, Agriculture Handbook No. 680, was made possible by the work of many people from around the country. Contributing authors include U.S. Department of Agriculture, Forest Service and Agricultural Research Service entomologists and pathologists, university professors and researchers, State extension specialists, consultants, and plant pathologists and horticulturists in private industry.

Using lidar in an area-based model-assisted approach to forest inventory has the potential to increase estimation precision for some forest inventory variables. This study documents the bias and precision of a model-assisted (regression estimation) approach to forest inventory with lidar-derived auxiliary variables relative to lidar pulse density and the number of sample plots. For managed forests on the Lewis portion of the Lewis-McChord Joint Base (35 025 ha, 23 290 forested) in western Washington state, we evaluated a regression estimator for combinations of pulse density (.05–3...

In the northeastern United States, both component and total aboveground tree dry-biomass estimates are available from several sources. In this study, comparisons were made among four methods to promote understanding of the similarities and differences in live-tree biomass estimators. The methods use various equations developed from biomass data collected in the United States and Canada. For hardwood species, estimates for biomass components tended to differ among the methods; however, the estimates for total aboveground biomass were more compatible. For softwood species, the biomass...

Gradient analysis is rarely used in studies of fungal communities. Data on macromycetes from eight sites along an elevation gradient in central Veracruz, Mexico, were used to demonstrate methods for gradient analysis that can be applied to studies of communities of fungi. Selected sites from 100 to 3,500 m altitude represent tropical dry forest, tropical montane cloud forest, conifer forest, and their ecotones. From May to October 2010, macromycetes were collected monthly within ten 10 × 10 m permanent plots per site. In total, 672 individuals of 213 species of macromycetes were recorded....

Context: Availability of public neighborhood parks is associated with physical activity. Little is known about how parks contribute to population energy balance. Purpose: This study estimated energy expenditure associated with the use of neighborhood parks and compared energy expenditure by activity areas within parks and by neighborhood race/ethnicity and income. Design: The System for Observing Play and Leisure Activity among Youth (SOPLAY), a direct observation approach, was used to estimate energy expenditure in 10 Tampa (Florida) parks and 19 Chicago (Illinois) parks. Setting: Parks...

Forest owners in Massachusetts (U.S.) live in a densely populated state and near forestland that is under pressure of development and characterized by small parcel size. Forest-based biomass harvesting in Massachusetts is a renewable energy topic generating a great deal of discussion among all constituents. To provide perspective on these discussions, our analysis asks how much forested land in Massachusetts could be available for biomass supply. This analysis considers the level of bioenergy production that could be maintained on an annual basis given the amount of woody biomass that is...

U.S. forests, including family-owned forests, are a potential source of biomass for renewable energy. Family forest owners constitute a significant portion of the overall forestland in the U.S., yet little is known about family forest owners' preferences for supplying wood-based biomass. The goal of this study is to understand how Massachusetts family forest owners feel about harvesting residual woody biomass from their property. The study estimates the probability that Massachusetts landowners will harvest biomass as part of a timber harvest using data from a survey of 932 Massachusetts...