Treesearch

A century of fire suppression across the Western United States has led to more crowded forests and increased competition for resources. Studies of forest thinning or stand conditions after mortality events have provided indirect evidence for how competition can promote drought stress and predispose forests to severe fire and/or bark beetle outbreaks. Here, we demonstrate linkages between fire deficits and increasing drought stress through analyses of annually resolved tree‐ring growth, fire scars, and carbon isotope discrimination (Δ13C) across a dry mixed‐conifer forest landscape. Fire...

Sugar maple (Acer saccharum Marsh.) decline was a major forest health challenge in northern Pennsylvania starting in the mid- to late 1980s and continued through the mid-1990s. During this time sugar maple suffered extensive crown dieback and rapid mortality, primarily on the unglaciated Allegheny Plateau in northwestern and north-central Pennsylvania (Drohan et al. 2002, Horsley et al. 2000). Declining trees exhibited a slow loss of vigor and increased fine twig dieback, which was followed by large branch mortality. This frequently ended in tree death (Kolb and McCormick 1993). Surveys...

Forest management decision support software has been used for several decades. Many people have tried a variety of approaches, with varying degrees of success, to provide information that helps forest managers make decisions. This chapter documents some of the successes and failures of NED and SILVAH. In 1988 the U.S. Department of Agriculture, Forest Service Northeastern Forest Experiment Station used its Genesis program to stimulate innovation. Under the leadership of H. Clay Smith, it convened the Stand Regeneration working group and, under the leadership of David Marquis, created the...

The iso/anisohydry concept characterizes plants according to their water status regulation. Coexisting definitions and misconceptions have recently led to considerable criticism. Here, we discuss reasons for the misconceptions and propose a robust definition of iso/anisohydry using the leaf turgor loss point to integrate the complex interplay of plant hydraulic traits.

Forests, particularly those on public lands, are managed for multiple resources. Forest resources include timber production, watershed protection, carbon sequestration, recreational opportunities, and wildlife habitat, among many others. For most nonindustrial private landowners, sustaining wildlife ranks higher than timber production as a forest ownership goal (Butler and Leatherberry 2004). Until recently, the SILVAH decision support system included only a very minor wildlife component, the ability to record stems as actual or potential den trees (Marquis et al. 1992). Wildlife informatio...

Foresters and wildlife managers have long known that forest management activities have impacts on wildlife communities (see Smith 1962). Research has also shown that private landowners often cite provision of wildlife habitat as one of their main reasons for owning forest land (Hodge 1996, Jones et al. 1995, Kluender et al. 1999). Direct census of wildlife populations is challenging and expensive, and until the late 1980s, publications developed to provide information on how forest management activities can benefit wildlife tended to focus on single species, especially game species, and...

Forests cover 8.2 million acres in Ohio, encompassing 31 percent of the state's land area (Widmann 2014). Eighty-three percent is privately owned; 17 percent is publicly owned. Most forest land is in the unglaciated southeastern area of Ohio and is dominated by oak-hickory forests (Fig. 1). These provide critical habitat for more than 100 wildlife species, which include at-risk animals such as wood thrush (Hylocichla mustelina), cerulean warbler (Setophaga cerulea), and timber rattlesnake (Crotalus horridus). The topography of these landscapes is highly dissected and creates spatially...

National greenhouse gas inventories often use variations of the gain–loss approach whereby emissions are estimated as the products of estimates of areas of land-use change characterized as activity data and estimates of emissions per unit area characterized as emission factors. Although the term emissions is often intuitively understood to mean release of greenhouse gases from terrestrial sources to the atmosphere, in fact, emission factors can also be negative, meaning removal of the gases from the atmosphere to terrestrial sinks. For remote and inaccessible forests for which ground...

The State Forest Inventory (SFI) in the Russian Federation is a relatively new project that is little known in the English-language scientific literature. Following the stipulations of the Forest Act of 2006, the first SFI sample plots in this vast territory were established in 2007. The 34 Russian forest regions were the basic geographical units for all statistical estimates and served as a first-level stratification, while a second level was based on old inventory data and remotely sensed data. The sampling design was to consist of a simple random sample of 84,700 circular 500 m2 sample...

In late 1999, the Pennsylvania Bureau of Forestry entered into a partnership with the USDA Forest Service's Northern Research Station to revise the SILVAH decision support system so that it would be more applicable to mixed-oak (Quercus spp.) forests. To expedite the revisions, the two agencies organized a committee of scientists and experienced field foresters who used relevant research results from other regions to devise interim inventory criteria and prescriptions. This approach accelerated the development process and facilitated acceptance of the interim guidelines in just a few...