Treesearch

This paper reports the first year survival and growth of red oak seedlings underplanted in two mixed upland hardwood stands in south central Iowa. The underplanted seedlings were undercut and not undercut 1-0 red oak stock. Fifteen blocks were laid out in 1990, with seven of the blocks receiving a foliar application of glyphosate herbicide. In the winter of 1990-1991, all non-oak trees were removed and their stumps treated with Picloram. Treatment areas were established in the spring (1991). The trials encompassed ten seedllings from each of three root classes: 0-4, 5-9, and ten or more...

Concerns of poor oak regeneration, changing climate, biodiversity patterns, and carbon cycling in the Central Hardwoods have prompted ecological and physiological studies of old-growth forests and their role in maintaining the landscape. To examine the effects of old-growth canopy structure on the physiological productivity of overstory and understory species, we measured physiological parameters of canopy trees in an old-growth oak-maple forest in east-central Indiana. Mid-day measurements of photosynthesis, transpiration, stomatal conductance, photosynthetically-active radiation,...

An analysis of recent trends in eastern U.S. hardwood lumber production indicates that total output increased sharply between 1977 and 1991. The increase, however, was much more pronounced in the East's northern tier of states than in the southern. This paper first examines recent hardwood lumber usage trends and historic hardwood lumber production trends. Changes in hardwood lumber production over the last 15 years are then related to changes in national hardwood lumber demand and regional differences in timber attributes.

Some physical, thermal, and chemical properties of bark of eleven tree species native to the central hardwood region were measured to determine their potential to protect the vascular cambium from damage by fire. The relationship between dbh and bark thickness for each of sixteen species was determined. For purposes of monitoring seasonal trends, two species (Quercus macrocarpa Michx. and Acer saccharinum L.) were sampled periodically during one growing season. Heat transfer through bark tissue of eleven species was monitored during simulated fires conducted in the field. Bark samples were...

Although sugar maple (Acer saccharum Marsh.) is not considered drought tolerant, it is common on xeric limestone glade-like sites in central Missouri. Acer saccharum on such sites may be a drought-tolerant ecotype or may have access to deep water supply through bedrock cracks. We investigated these possibilities during the 1990 growing season by comparing water relations and photosynthetic rates of A. saccharum trees growing on glade-like and typical upland sites.

The Karner blue butterfly, Lycaeides melissa samuelis Nabokov, became federally listed as endangered in 1992 and is thus afforded protection under the Endangered Species Act of 1973. This insect has a very discontinuous range, with 1992 populations found in Minnesota, Wisconsin, Illinois, Indiana, Michigan, New York, and New Hampshire. Karner blue larvae feed exclusively on wild lupine, Lupinus perennis L., a disturbance-adapted plant common to oak savannas, pine barrens, and lake dune complexes. Historically, Karner blue sites have been maintained by fire. Besides lupine, the Karner blue...

To maximize forest production, foresters need to plant the best genotypes provided by forest geneticists. Where should the forest geneticist search for the best seed sources? How far can one go south, or north to find them? The answer may rely on the species and the location of the test plantation. For example, when black walnut trees were tested in Illinois, Indiana, Missouri, and southern Michigan, trees from southern seed sources grew faster than those of local and northern seed sources. However, in Iowa and Minnesota, trees from northern sources were generally larger than trees from...

Of 603 central Pennsylvania plots that were established in 1978 to measure the short-term impact of repeated gypsy moth (Lymantria dispar) defoliation, 228 were selected for continued study in 1985. Individual observations of defoliation and tree vigor were continued through 1992. Although two gypsy moth outbreaks occurred across central Pennsylvania from 1978 to 1990, only 22% of the plots were defoliated severely for more than one year. Net change in basal area/acre from 1978 to 1990 (including both accretion and ingrowth) ranged from +70 to -92% depending on defoliation severity and...

Pear thrips, Taeniothrips inconsequens (Uzel) (Thysanoptera: Thripidae), were first positively identified as causing damage to sugar maple (Acer saccharum Marsh.) in forest environments in the United States in 1980. Damage in Pennsylvania from this insect has occurred consistently since 1980, with the most extensive impact in 1988 (0.5 millon ha). Sap characteristics and crown condition were monitored for three years following a 1989 thrips attack in a Pennsylvania sugarbush on 56 trees representing a range of thrips damage. Heavy damage in 1989 was associated with increased crown transpare...

Phenological patterns, light conditions, and photosynthetic activity of Ohio buckeye and sugar maple foliage on trees in the forest understory were monitored and compared over two growing seasons in two mesophytic upland woodlands in central Illinois. Ohio buckeye began leaf expansion three to four weeks earlier than sugar maple, started leaf senescence and shedding in July, and had lost all leaves by September 1. Sugar maple began senescence in September and lost its leaves by the end of October. Thirty percent area inventories of both Ohio buckeye and sugar maple vegetation on both...