Treesearch

Dissections of 50 branch stubs from seven black walnut trees revealed that some discolored wood was associated with all stubs, and that ring shakes and dark bands of discolored wood were associated with 14 of 17 stubs that were "flush cut" (branch collar removed) 13 years earlier while they were living or dead. Ring shakes formed along the barrier zone tissues that separate the wood formed before wounding from wood that formed subsequently. Pruning done early in the life of the tree eliminates these problems. When pruning is done late in the life of a tree, care must be taken not to remove...

This paper presents positive and negative attributes of GYPCHEK for evaluation by land managers contemplating gypsy moth control. Special precautions and procedures are outlined. Environmental and ecological considerations are discussed and results to be expected from the use of GYPCHEK in gypsy moth control are presented.

The production of flowers and seeds of black cherry, red maple, sugar maple, and white ash and their relation to advance regeneration were observed from 1971 through 1976 on the Allegheny Plateau of northwestern Pennsylvania. There were good seed crops 1 year out of 2 for black cherry, 1 year out of 3 for red maple, and 1 year out of 6 for sugar maple. No white ash seed was produced. Flower crops were reliable indicators of seed crop size for the maples but not for black cherry. Both seed production and advance regeneration were related to basal area. Advance regeneration and basal area...

Results of a breeding program in which a large number of pine species were tested indicate that a number of species and hybrids may be useful in the northeastern United States. Austrian black pine x Japanese black pine and hybrids containing Japanese red pine all had good growth rates. While none of the soft pines grew faster than eastern white pine, a number of hybrids grew equally fast and the nonnative component in the crosses may provide pest resistance, which is the number one problem in the Northeast.

Diameter growth rates of the 40 largest trees per acre on 154 permanent plots in Kentucky, Ohio, Missouri, and Iowa were analyzed to determine the effects of thinning in upland oak stands. The plots were established over a wide range of stocking levels, stand age, and site conditions. Thinning resulted in increased diameter growth of the residual trees, regardless of age or site. The heavier the thinning, the greater the response. Diameter growth rates, and growth response after thinning relative to a control, were better in younger stands. Growth rates were higher on better sites, but the...

A cost analysis of processing maple sap to syrup for three fuel types, oil-, wood-, and LP gas-fired evaporators, indicates that: (1) fuel, capital, and labor are the major cost components of processing sap to syrup; (2) wood-fired evaporators show a slight cost advantage over oil- and LP gas-fired evaporators; however, as the cost of wood approaches $50 per cord, wood as a fuel would no longer have this cost advantage; (3) economies of scale exist in processing maple sap to syrup; (4) in 1977 the total cost of production, including both sap production costs and processing costs, for a...

An oak soil-site productivity equation was developed for the well-drained, upland soils in the northwestern portion of West Virginia adjacent to the Ohio River. The equation uses five easily measured soil and topographic variables and average precipitation to predict site index. It accounts for 69 percent of the variation in oak site index and has a standard error of 4.3 feet at the mean site index of 67.6 feet. The equation was tested with data from 61 independent plots, and the results showed a correlation of 0.83 between predicted and observed site indexes.

Results of two independent studies were analyzed to determine whether residual stocking after thinning had any effect on change in stem form of upland oak. One study is based on 15 years' change in Girard Form Class after thinning of an 80-year-old white oak stand in eastern Kentucky. The other, 12-year changes in Girard Form Class and breast-height form factor based on Barr and Stroud Dendrometer measurements in 35-year-old thinned upland oak stands in Ohio, Kentucky, and Missouri. Sample trees in both studies were in the dominant and codominant crown classes. Neither study showed any...

Height growth of silver maple, white ash, yellow-poplar, sycamore, eastern cottonwood, and white spruce seedlings was not significantly influenced by 0.15 ppm SO2 for 8 hours/day, 5 days/week. A fumigation treatment of 0.25 ppm SO2 for 8 hourd/day, 5 days/week did not significantly affect height growth of black alder, yellow-poplar and white spruce seedlings but significantly reduced the height growth of eastern cottonwood, green ash, and sycamore seedlings. Exposure to toxic concentrations of SO2 (1 to 4 ppm) for 2 to 8 hours significantly affected the height growth and caused leaf injury...

This paper reports the results of the 1978 aerial test with the gypsy moth NPV product, GYPCHEK. Although a general population collapse was observed, conclusions could be made on the efficacy of three formulations and two aircraft nozzling systems. The molasses formulation was more effective when applied with Beecomist® nozzles, but Pro-tee® formulations were more effective when applied with Flat Fang® 8006 nozzles.