Treesearch

Portions of the lower bole of occasional sugar maples (Acer saccharum Marsh.) in Lake States northern hardwood stands are sooty black in sharp contrast to the normal gray. The blackened areas may encircle the entire stem or be confined to a narrow band; they have been observed as high as 25 feet but generally extend about 15 feet above the ground. Preliminary investigations indicated that nearly all such trees had been heavily and repeatedly attacked by sapsuckers. The possibility of using the black bark as an external indicator of bird peck defect in sugar maple prompted this investigation.

Water storage characteristics of the various horizons in a northern Minnesota bog were found to vary considerably with peat type. Surface horizons of sphagnum moss contain 0.020 g. per cc. of dry material and 95 to nearly 100% water by volume at saturation. Its total porosity consisted primarily of large pores which released 0.80 cc. of water per cc. between saturation and 0.1 bar suction. Decomposed and herbaceous peats from horizons below 25 cm. had water-holding properties strikingly different from those of the moss peats. These materials had bulk densities of 0.24 and 0.14 g. per cc.,...

Most of the stream-discharge records for our experimental watersheds are taken by continuous measurements. But the question arises: are continuous measurements necessary to determine effects of forest treatments? Or could treatment effects be determined by measurement of discharge at intervals, say, once a day or once a week?

Many studies, using various methods, have been made of dew deposition to determine its importance as a source of moisture. For example, Duvdevani (1947) used an optical method in which dew collected on a wooden block was compared with a set of standardized photographs of dew. Potvin (1949) exposed diamond-shaped glass plates at 45º to ground level, so that condensed dew ran into a graduate. Lloyd (1961) studied amount and duration of dew by using polystyrene blocks mounted on a balance linked to a 7-day continuous recorder. Craddock (1951) devised a sub-groundlevel balance and recorder to...

In attempts to find a chestnut tree that is resistant to the blight fungus Endothia parasitica, Asiatic chestnuts have been imported and grown in this country, and tree breeders have worked to produce hybrid trees that might be suitable substitutes for the blight-susceptible American chestnut, Castanea dentate, in timber and nut production.

In Pennsylvania and New York there are 2,350,000 acres of plantable land that could be utilized for growing timber for future needs. Much of this plantable land lies on the Allegheny Plateau - a region that is eminently suited to growing black cherry (Prunus serotina Ehrh.). On the Allegheny National Forest alone, 26,000 acres are classed as plantable. Besides this, the even-aged management program recently adopted on the Forest calls for clearcutting about 3,000 acres each year. Although these cut areas are expected to regenerate naturally for the most part, some of the acreage very...

The production of maple sugar and maple syrup from the sap of the sugar maple tree (Acer saccharum Marsh.) is an important industry in the Northeast, particularly in Vermont and New York. Although it has been recognized for a long time that some trees are sweeter than others - have a higher sugar content in their sap - systematic study of ways to improve sugar production by this species was begun only rather recently.

Although sweetgum (Liquidambar styraciflua L.) is one of the most valuable hardwoods in bottomland forests from southern New Jersey and southern Illinois southward, relatively little is known about its production and distribution of seed. Knowledge of both is essential in planning successful measures for reproducing the species. To provide some of the needed information, the Northeastern Forest Experiment Station studied the production and distribution of sweetgum seed in 1962 from four New Jersey stands.

During the period 1946-49, The Pennsylvania State University established 22 experimental plantings of trees and shrubs on strip-mine spoil banks in the Bituminous Region of Pennsylvania to determine which species were best suited for revegetating such sites. When 10-year growth on the experimental plots was evaluated, a clone of hybrid poplar was found to have outgrown all the other species tested. The performance of this one hybrid poplar suggested that other hybrid poplars might be well adapted for growing on strip-mine spoils, so we planned a screening test of as many hybrid poplar...

Although infrequently used, the trough-type rain gage has been described as aerodynamically the most efficient of gages (Hayes and Kittredge 1949). This applies only to the commercial semicircular eave-gutter type of trough and not to troughs rectangular in cross-section. The latter, as well as the upright cylindrical type of gage, produces greater disturbances in the rain-bearing wind stream.