Treesearch

The knowledge of the rate at which trees grow in virgin forests, after clear cutting and under selective logging, is indispensable in any forest calculations or forest practice. The enactment of the Forest Crop Law, which brought under its operation about 175,000 acres of cut-over land during the first year, the example set by several progressive lumbermen in selective logging, and the general public interest in the future of the cut-over land focused attention acutely on what may be expected from cut-over land in the way of growth and returns in the course of the next few decades.

Damping-off is the commonest English name for a symptomatic group of diseases affecting great numbers of plant species of widely separated phylogenetic groups. It is commonly used for any disease which results in the rapid decay of young succulent seedlings or soft cuttings. Young shoots from underground rootstocks may also be damped-off before they break through the soil.

Incense cedar (Libocedrus decurrens) is of considerable economic importance on the Pacific coast. The available supply of this species, which never occurs alone but always in mixture, chiefly with yellow pine, Jeffrey pine, sugar pine, Douglas fir, and white fir, averaging about 8 per cent of the stand, although often forming as high as 30 to 50 per cent, is estimated at 11 billion feet, 10 billon of which occurs in California.

The best thing that can be said of any dry kiln is that when it is run by a properly informed operator the temperature, humidity, and circulation are constant and uniform. In an endeavor to produce a kiln in which each of these could be regulated independently of the others, the Forest Products Laboratory designed and developed the "Forest Service Humidity Regulated Water Spray Kiln," described in this bulletin.

Jack pine is a very frugal tree in its climatic and soil requirements. The northern limit of its natural range is within 14 degrees of the Arctic Circle and the southern is marked by the southern shores of Lake Michigan. No other North American pine grows naturally so far north and all the others grow farther south. It develops commercial stands and reproduces itself on dry, barren, sandy ridges and plains unsuited to other native trees. The seed germinates more quickly and grows more rapidly in its early years on lumbered and burned-over forest land and on idle, worn-out, cleared land...

The right handling of the home forest has come to be a matter of recognized importance in farm management. Farming touches forestry at a number of different points. The farm requires timber for the building and repair of houses, barns, sheds, fences, and telephone lines. It needs more or less wood for fuel, and it should have some woodland also for protecting the soil against erosion on steep slopes, for shelter for growing crops and livestock against the hot, dry wmds of midsummer, the cold winds of winter, and likewise for the comfort of man and the home of game animals.

Sycamore is one of the important commercial woods of the United States, and is of special value for use in certain containers, such as slack barrels and plug-tobacco boxes. It ranks low, however, in amount consumed, for about 25 native woods, including 13 hardwoods, are used in larger quantities. This bulletin gives information on the supply of sycamore, on the conditions attendent on its manufacture, and on how it may be used most advantageously.

In this bulletin, which is one of an annual series covering the period 1904 to 1918, inclusive, with the exception of 1914, are detailed statistics of the 1918 production of lumber, lath, and shingles in the continental United States, with comparative figures from previous annual reports.