Treesearch

Bark thickness for sugar maple trees in Vermont was found to be related to tree diameter at breast height (d.b.h.). The relationship was positive-as the diameter increased, the bark thickness increased.

Using the internal rate of return concept to rank the economic desirability of investment opportunities can lead to incorrect investment decisions. Present value provides a correct and unambiguous means of judging such investment alternatives.

Growth of six isolates of Fusarium solani on potato dextrose agar was determined with (1) continually changing temperature programs, (2) programs consisting of two alternating constant temperatures, and (3) a constant temperature program. All programs had a mean of 70º F. Growth increased with an increase in temperature fluctuation of 10 or 20ºF., but decreased with a fluctuation of 40º F. Significant differences were found in the growth rates of the isolates.

A method of apportioning the maximum dollar value gain from tree growth into the amounts contributed by diameter growth, merchantable height increase, and quality improvement is described. The results of this method are presented for various sizes and qualities of yellow-poplar trees.

A greenhouse trial was made to determine the effect of three rates of liming on the growth of five species of pine seedlings in an extremely acid strip-mine spoil. Liming at the rate of 5 tons per acre-foot significantly increased the growth of four of the species. Tissue analysis indicated the growth rate may be related to a reduction in the concentration of the metallic ions of manganese, iron, copper, and zinc.

Small numbers of 10 species of wood-boring insects were reared from newly hatched larvae to adults on artificial media with good survival. Species with life cycles of up to 2 years in nature were reared on the media in less than 1 year. Although all of the adults appeared normal physically, some were sterile. One species was reared artificially for three generations. Survival figures and the developmental periods of the larval stages are given.

A study of yellow-poplar seedlings showed that early survival and growth were best among stems that originated in May and early June. Few, if any, seedlings that emerged after 1 July were in favorable competitive condition 3 years later. This indicates that clearcuttings made for maximum natural regeneration of yellow-poplar should be carried out in fall and winter to permit early germination in the spring.

Product specifications were fed into a computer so that the yield of products from the same sample of logs could be determined for simulated sawing methods. Since different sawing patterns were tested on the same sample, variation among log samples was eliminated; hence, the statistical conclusions are very precise.

This report presents 1967 forest resource statistics for the Hill Country-Ohio's portion of Appalachia. The Hill Country comprises 28 counties, which were divided into three geographic sampling units for this survey. The Hill Country of the 1952 Ohio forest survey contained 26 of these counties. The additional Appalachia counties are Brown and Clermont in the South-Central Geographic Unit. The Southeastern and East-Central Units are the same as they were in the first survey. To facilitate making comparisons between inventories, we have adjusted 1952 Hill Country data to include Brown and...

Not all black walnut trees grow in the forest. Many are found in open places - along fence rows, in pastures, in narrow wooded strips. Trees in places like this are not counted in the forest surveys made by the U. S. Forest Service to find out how much timber we have. Yet such trees are part of our overall black walnut resource. The U.S.D.A. Forest Service undertook a study to find out how much black walnut (Juglans nigra L.) timber there is in these nonforest areas. The study was made in Kentucky for two reasons. First, because Kentucky produces a lot of black walnut. Second, because a...