Treesearch

The Siberian moth, Dendrolimus superans Butler (Family Lasiocampidae), is the most destructive defoliator of conifer forests in Northern Asia. Outbreaks defoliate millions of acres and occur at intervals of 8 to 11 years. The larvae feed on most conifers in the pine family, but outbreaks occur in fir, spruce, Siberian pine, and larch forests. The biology of the Siberian moth is unusual and complex, and it has been difficult to control in its native habitat. There are no known introductions of the Siberian moth to North America.

Distribution-of-cut guidelines describe the amount of stand density to be removed from broad size classes of trees to attain a target residual stand density and stand structure. Current guides for thinning Allegheny hardwoods recommend that 75 percent of the cut relative stand density be taken from below the average stand diameter and 25 percent from above. These guides are well suited for maximizing production of wood volume and stand worth in 50-year-old stands. In 70-year-old stands, previously thinned or not, wood production is maximized by distributing the cut so that the entire cut...

Soil fumigant efficacy in forest-tree and ornamental nurseries depends on the tillage tool used for incorporation. Maximum depth and uniformity of incorporation of surface applied materials by three rotary tillers and a spading machine were compared in a loamy sand nursery using ceramic-sphere tracers (1-3 mm diameter) and dazomet (tetrahydro-3,5,dimethyl-2H-1,3,5-thiadiazone-2-thione) micro-granules. Depth of incorporation in the top 30cm of soil was evaluated by (1) recovery of incorporated spheres in 2cm increments, (2) biocidal activity in 6cm increments, and (3) cone resistance by...

Long viewed as a center of ecological restoration activity, over the past year the Chicago region has also gained notoriety as a center of ecological restoration controversy. After years of operating in relative obscurity, public agencies and private groups engaged in restoring metropolitan forest preserve sites have now drawn considerable attention from the press and some individuals and groups. While much of this attention has been positive, opposition to restoration has been so effective that, at the time of this writing, partial moratoriums on restoration activity have been imposed in...

Limesink wetlands are a common aquatic habitat in southwest Georgia, USA. These wetlands are non-alluvial, occupying shallow depressions formed from dissolution of limestone bedrock and collapse of surface sands. They are seasonally inundated, with a typical hydroperiod extending from late February to early July. Little is known about factors influencing invertebrate community structure in limesink wetlands. Recently, it has been suggested that regular inundation and drying are important influences on community structure in some seasonal wetlands. We had an opportunity to examine this...

In the early 1990s managers in natural resource agencies in Missouri began asking, "How does ecosystem management relate to our current practices? How might we do a better job of managing large ecosystems?" As they started addressing these questions, several points emerged: Planning and managing ecosystems requires expertise in more subject areas than any single individual can possess. Many ecosystem attributes can be observed only at large scales, like landscapes or watersheds. Management issues also involve multiple ownerships. New tools are needed to help synthesize information and...

Forest management practices imposed at one spatial scale may affect the patterns and processes of ecosystems at other scales. These impacts and feedbacks on the functioning of ecosystems across spatial scales are not well understood. We examined the effects of silvicultural manipulations simulated at two spatial scales of management planning on landscape pattern and assessed the implications for forest-interior bird species. Landscape context was taken into consideration in determining harvest locations in the landscape-base management planning scenario but not in the stand-base planning...

Disturbances such as windthrow, fire and timber harvest significantly effect how forest ecosystems develop. We have and continue to modify the nature of our forests through anthropogenic fire, fire suppression, and resource exploitation and management. Past disturbance histories, as well as current cultural practices and ecological processes, must be considered in order to improve our understanding of the dynamic nature of our forest systems and our ability to predict future forest conditions. Unfortunately, site-specific records of past land use practices and disturbance regimes are often...

Red oak seedlings were underplanted in a closed-canopy mature northern hardwood stand and an adjacent shelterwood in central Ontario. Overstory density effects on seedling survival and growth were assessed 2 yr after planting. After 2 yr, seedling survival was 90% in the uncut stand and over 99% in the shelterwood. Seedlings in the uncut stand experienced negligible or negative annual increments in stem diameter and height. Seedlings in the shelterwood were about 2 mm larger in diameter and nearly twice as tall as those in the uncut stand after 2 yr. Second-year stem diameter and height...

This paper describes a new approach for monitoring the social environment for forestry. Computer methods were used to analyze almost 30,000 online news media stories about the national forests for expressions of four main categories of benefits and values. Recreation benefits and values were expressed more often than other categories, both at the national and regional levels, followed by commodity, ecological, and moral/spiritual/aesthetic benefits and values. A slight downward trend was found in expressions of commodity benefits and values at the national level.