Treesearch

Exotic species invasions, called by one conservation biologist the "least reversible" of all human impacts, cause harm to economies (e.g., fisheries, wildlife populations, tourism), the environment (e.g., in the form of broadcast of pesticides and herbicides), human health and wellbeing (e.g., allergic responses and the increase in fire severity in some landscapes), and aesthetics (e.g., the amount of mortality in vegetation). These invasions threaten biological diversity by causing population declines of native species and by altering key ecosystem processes like hydrology, nitrogen...

The Exotic Pest Plant Council (EPPC) is a proactive organization established to raise awareness about the threat posed by invasive exotic pest plants in natural areas and acts to stop the continued spread of invasive species. EPPC provides fora for sharing information and provides networking opportunities regarding all matters concerning this issue. EPPC was first established in Florida in 1984 and has since become established in California, the Pacific Northwest, and Tennessee. These independent organizations have formed the National Association of Exotic Pest Plant Councils. The different...

Invasive exotic pest plants, diseases, and insects, have had a dramatic impact on the health and composition of the Eastern forests for many decades. Chestnut blight was discovered in the United States in 1904. Since then, it has virtually destroyed the chestnut population, which once occupied 25 percent of the eastern forest. In the 1860's, the gypsy moth was accidentally released in Massachusetts. Since then, it has become established in 16 states, and for most of the past 15 years, has defoliated a million acres of hardwood trees each year. Kudzu was introduced into the United States in...

Effects of seasonal prescribed fires of varying intensities on density, mortality, stem form, height, and height growth of hardwood advance regeneration were investigated. Three mixed-hardwood stands on productive upland sites were cut using a shelterwood technique, each forming a block of spring burn, summer burn, winter burn, and control treatments. Advance regeneration was inventoried from permanent plots before and after burning. Fires top-killed nearly all hardwood regeneration, forcing the rootstocks to sprout. Fire treatments reduced densities of all hardwood species relative to not...

Gypchek, a registered microbial insecticide for aerial and ground-based application against the gypsy moth, Lymantria dispar L., was field-tested in 1996 and 1997 at 2 doses (1011 and 1012 polyhedral inclusion bodies (PIB) per 379 liters (100 gallons) ) and with and without a sunscreen. An in vitro-produced strain of gypsy moth virus was tested in 1997 at the 1O11-PIB dose; however, the effective dose was lower because in vitro-produced PIBs contained 5-fold fewer virions than Gypchek PIBs. Treatments were applied to overstory oak, Quercus spp., trees with a truck-mounted hydraulic...

In previous studies on the formation of Lymantria dispar nuclear polyhedrosis virus (LdMNPV) few polyhedra (FP) mutants, several polyhedron formation mutants (PFM) were identified that appeared to be unique. These viral mutants are being characterized to investigate the processes of polyhedron formation and virion occlusion. LdMNPV isolate PFM-1 is one of these mutants, and is described in this report. Genetic techniques were used to determine if isolate PFM-1 contained a mutation in the polyhedrin or 25K FP gene.

Foresters in the Northeast are both blessed and cursed by the inherent complexity of the region's forests. Thousands of years may pass between natural stand-replacing disturbances, though partial disturbances, such as blowdown, defoliating insects, and various forms of partial cutting, are common (Seymour 1995). Foresters in the region typically deal with multiaged stands and often seek to maintain or enhance structural diversity through selection cuttings. Selection forestry is complicated and prone to misapplication, however, especially in the mixed-species stands that dominate this...

Allegany State Park in southwestern New York State attracts visitors from across western New York State, and neighboring states and Canada, while providing a variety of valuable ecological, social, and recreational benefits. Proposed management of forested park land has generated considerable controversy. Conflicting values regarding older growth versus mixed age forests, conflicting needs of alternative recreational activities, and the potential benefits of harvesting valuable timber underlie this controversy. There has to date been no attempt to estimate direct economic impacts of the...

The International Union for the Conservation of Nature has drafted guidelines to help managers of protected natural areas to develop economic arguments in defense of those areas. The guidelines identify a series of benefits which protected areas might produce and which all have real markets in the outside world, and recommend that managers focus their arguments on these benefits. One of the benefits, tourism spending, cannot be treated as a benefit like the others, however, and there are additional benefits which the authors believe should be included in the guidelines

Management of trails has become challenging as funding for their operation and administration has decreased. To contend with shortfalls, resources managers are forming partnerships with stakeholders to meet these challenges. An investigation of two trail programs in Michigan is used to illustrate the benefits of partnerships, key elements related to success, and challenges associated with partnerships.