Treesearch

In forestry, the tools to carry out on-the-ground management are found in the toolbox of silviculture, that is, the part of forestry that deals with the development and care of forests. This development and care can be all encompassing, including establishment, growth, composition, health, and quality of trees and stands to meet the diverse needs of society. The planned program of all these activities, spanning the entire life of a forest stand, is termed a silvicultural system. Ostensibly, such a definition for silviculture would seem to recognize most forests, outside of plantations, as...

Red pine (Pinus resinosa Ait.) ecosystems of the western Great Lakes region of United States and Canada are the focus of this chapter. These forests are found in northern Michigan, Wisconsin, and Minnesota in the United States, and portions of southern Ontario, Canada. Historically, because of high economic value of red pine, this ecosystem has been managed using a timber-focused silvicultural system in both plantations and natural-origin stands, generally based on even-aged regeneration systems followed by planting of red pine. The timber-focused model results in composition and structure...

Elements of ecological silviculture have been in existence for over a century [l], yet many of the principles and applications did not emerge broadly until the 1990s (e.g. [2]), with particular emphasis on Douglas-fir-dominated forests of the Pacific Northwest [3]. The chapters in this book highlight how far this silvicultural model has evolved over the past several decades, both in geographic extent and the diversity of forest ecosystems and management contexts for which natural models have been applied. In contrast to generic mischaracterizations of ecological silviculture as solely...

This chapter focuses on the largely oak (Quercus)- dominated forest, woodland, and savanna eco-systems that characterize the Central Hardwoods Region. These ecosystems occur across much of the eastern United States, including five ecoregion provinces (Figure 16.1) [1, 2].The Central Hardwoods Region contains productive agricultural land and a high proportion of the population of the United States. Approximately 75% of the forest land is privately owned [3], exceeding 90% in many states. Fragmentation continues to decrease the size of privately owned forests and woodlands with average area...

Plastic pollution is a significant conservation issue and represents a significant threat to wildlife in marine and aquatic systems. Less understood is plastic pollution in terrestrial systems, especially those that are remote and/or protected. Here, we document the surprising discovery of the plastic bristles of a hairbrush embedded in the haypile of an American Pika (Ochotona princeps) in a remote area of Glacier National Park, Montana. We hypothesize that the bristles of the hairbrush, given their appearance, may have been perceived by the pika as herbaceous plant material that could...

Membranes are a selective barrier that allows certain species (molecules and ions) to pass through while blocking others. Some rely on size exclusion, where larger molecules get stuck while smaller ones permeate through. Others use differences in charge or polarity to attract and repel specific species. Membranes can purify air and water by allowing only air and water molecules to pass through, while preventing contaminants such as microorganisms and particles, or to separate a target gas or vapor, such as H2 and CO2, from other gases. The higher the flux and selectivity, the better a...

The building industry requires the development of a ductile lateral force–resisting system made of mass timber to allow mass timber to continue to grow in popularity as the primary structural building material. A timber frame with mass ply lam (MPL) beams and columns with a timber buckling-restrained brace (TBRB) was subjected to a quasi-static cyclic loading protocol defined according to the qualification procedure of conventional buckling-restrained braces (BRBs). Two of the TBRBs in this study included a carbon fiber–reinforced polymer (CFRP) wrap to help confine the two ends of the...

Diaphragms transfer the forces exerted by lateral loads to vertical elements through an in-plane shear action. Cross-laminated timber (CLT) has garnered considerable interest as a diaphragm material, particularly for midrise nonresidential construction. This article discusses the findings of tests performed on two full-scale 6.1 m (20 ft) × 6.1 m (20 ft) cantilever CLT diaphragms composed of three-ply CLT panels. The diaphragms were subjected to in-plane shear loads with a cyclic loading protocol. Two different layouts of CLT panels were considered for this study (simple span and two-span...

Plants display a range of temporal patterns of inter-annual reproduction, from relatively constant seed production to “mast seeding,” the synchronized and highly variable interannual seed production of plants within a population. Previous efforts have compiled global records of seed production in long-lived plants to gain insight into seed production, forest and animal population dynamics, and the effects of global change on masting. Existing datasets focus on seed production dynamics at the population scale but are limited in their ability to examine community-level mast seeding dynamics...

Shortleaf pine (Pinus echinata) is an economically and ecologically important species that was once prevalent across the Southeastern United States, and there is growing interest in its restoration throughout its former range. One challenge with restoring shortleaf pine is competition from hardwoods. This study used tree-ring analysis to study growth response of shortleaf pines planted following a 2002 tornado in two stands with different known histories of management activities, specifically prescribed burning and mechanical release, across a range of competition levels. Early release was...