Treesearch

Diurnal changes in carbohydrate concentrations in leaves and current-year stems of a mature sugar maple tree were studied in June and September. In leaves, alcohol-soluble sugar concentration was highest in the morning and lowest in late afternoon or early evening; diurnal changes in starch lagged about 5 hours behind changes in sugar. Carbohydrate concentrations in current-year stems did not vary diurnally. Leaves weighed much more than current-year stems and contained a higher concentration of sugar and starch. In leaves, sugar concentration was higher in September than it had been in...

The impacts of forest cutting upon understory vegetation were evaluated for Ozark oak-hickory and Appalachian oak-pine stands. These findings were related to similar information from other eastern forest types. Production of understory vegetation is related to stand type, stand structure, stand disturbance, and site. Stand type, structure, and site operate together to influence the understory of uncut stands. Cutting the stand increases the amount of understory vegetation, but this increase is regulated by site quality, stand type, and structure. Unless undetected changes are occurring in...

A study was begun in 1965 to determine the effect of lime fertilizer, and mulch on the establishment and growth of crownvetch crowns planted on anthracite coal-breaker refuse. After 7 years the lime application had by far the strongest effect. Both 2.5 and 5.0 tons per acre increased survival and ground cover manyfold, and both treatments were equally beneficial from the first to the seventh growing season. The benefits of fertilizer and mulch were much less. Lime raised the pH to the neutral range, and this range was still the same 7 years after treatment. Exchangeable Ca and Mg were...

Woody reproduction 12 years after a seed-tree harvest cutting was evaluated for three central Appalachian hardwood sites in West Virginia, including species composition; size, number, and distribution; stem quality; effects of early cultural treatments; and influence of grapevines. Reproduction ranged from 1,250 to 1,700 stems per acre in the 1.0 to 4.9 inch dbh size class. Partial estimates revealed that about 250 potential dominant and codominant crop trees per acre were present on oak site index 70 and about 500 on site index 60. Sweet birch, sugar maple, yellow-poplar, and black cherry...

Laboratory tests were conducted with a standing wave tube to measure the acoustic absorption of normally incident sound by the bark of six species of trees. Twelve bark samples, 10 cm in diameter, were tested. Sound of seven frequencies between 400 and 1600 Hz was used in the measurements. Absorption was generally about 5 percent; it exceeded 10 percent for only three samples, and then only at 1250 Hz or above. No general trend was evident in the variation of absorption with frequency.

To determine the GVW and axle weights of tandem-axle logging trucks hauling into two West Virginia sawmills, 543 truckloads of hardwood sawlogs were weighed. The results showed that less than 2 percent of the truckloads exceeded the 48,000 pound GVW limit. While 58 percent of the truckloads exceeded the 32,000 pound tandem-axle weight limit, the front-axle weights never exceeded the 18,000-pound single-axle limit and seldom exceeded 10,000 pounds. Because the trucks sampled carried an average of 93 percent of the load weight on the rear axles, they could not haul maximum payloads without...