Treesearch

A method is described for collecting gas samples from tree trunks by placing a permanent probe in the tree and withdrawing samples with a portable vacuum pump. Marked quantitative differences were found between the concentration of gases in tree trunks and the concentration of gases in the atmosphere.

A study of growth at d.b.h. among eight hardwood species after partial cutting in second-growth stands. Red oak grew fastest, followed in order by yellow-poplar, sugar maple, basswood, black cherry, white ash, beech, and chestnut oak.

Describes a technique based on the use of a hypodermic needle for determining sap-sugar concentrations in small trees. The technique is applicable to pot cultures in greenhouses and also, with the use of a movable shelter, to seedlings in nursery beds.

Open-pit or strip-mining - primarily for coal - has expanded rapidly in eastern Kentucky during the past 15 years. Information about the amount, location, and general characteristics of the disturbed areas is necessary for appraising the economic impacts and overall effects of strip-mining in that section of the state, for planning reclamation programs, and for determining research needs and priorities. To obtain reliable estimates of the acreage disturbed both by the mining itself and by the associated coal-haul roads, and to provide relevant information about the disturbed areas, a...

Red oaks and yellow-poplars in a stand of second-growth cove hardwoods in West Virginia were studied to determine whether visible dormant buds are related to tree size or log position. No correlation was found between dormant buds and tree size, for either species; but yellow-poplars had a significantly greater number of buds on the upper log.

Black cherry trees that had large crown ratios and were 4 to 6 inches d. b. h. were pruned to various heights. Epicormic sprouting was severe and diameter growth at breast height was reduced on trees pruned to 75 percent of their height. Most trees pruned to 50 percent show little or no adverse effect after 3 years.

In 17 areas, mostly in the Coastal Plain and Piedmont sections of New Jersey and Maryland, treatments were made to favor the establishment and growth of yellow-poplar reproduction. Results emphasize the importance of fairly large overstory openings (preferably 1 acre or more) and of reductions in understories by mistblowing, burning, or disking, but show that seedbed preparation is needed only in areas borderline because of deep litter, scant seed supply, or dense herbaceous growth.

Early findings from a 5-year panel survey of New England campers' changing leisure habits are reported. A significant number of campers interviewed at four commercial campgrounds differed in their camping behavior from campers at four state park and national forest campgrounds. The most apparent differences are the higher degree of mobility and the larger dollar investment in camping equipment of the commercial campground visitors.

It is not generally recognized that a serious bias arises in the estimates of annual ingrowth and accretion, two of the growth components available from continuous forest inventory (CFI). The bias is demonstrated, and suggestions for correction are given.

Because bark thickness of sugar maple trees varies considerably, the depth of tapholes for collecting maple sap should be varied accordingly to get the taphole depth that will produce the best sap flow. A system of removable collars on the drill bit is recommended as a means of regulating taphole depth in research studies.