Our national forests

by Richard H. D. Boerker

Forest Protection Studies. Studies in forest protection endeavor to find the best methods of protecting the National Forests from fire, grazing, disease, insects, wind, snow, hail, and animals. The most efficient protection of the National Forests from fire calls for an accurate, scientific knowledge of all the factors that enter into the problem. Comprehensive studies are undertaken to secure the basis for a more scientific method of distributing National Forest fire-protecting funds. The aim has been to find the degree of intensiveness in fire protection warranted by timber, forage, and watershed values, as modified by their susceptibility to damage by fire. Under the ideal system of allotting fire-protecting funds, the most valuable resources, which at the same time are most in danger of destruction by fire, should receive the largest amount of funds and therefore the greatest amount of protection. Less valuable resources, less susceptible to fire danger, should receive protection in proportion. Other classes of fire protection studies have to do with the various phases of fire prevention, fire detection, and fire control. Studies have also been carried on to determine the rapidity with which fire spreads in different forest types, and under a given set of climatic conditions.

Protection from Grazing Damage. Studies of the effects of grazing upon the natural reproduction of forests are conducted with a view to devising a system of range control which would minimize such injury without requiring the total exclusion of the stock from the range. Studies have shown that serious damage occurs to seedlings under four feet in height during the dry season, on areas containing poor forage, or which have been overgrazed, or where there was little or no underbrush. It was found that sheep do twice as much damage as cattle. Some of the measures that have been adopted to lessen the injury to reproduction by sheep and cattle are: the revegetation of overgrazed areas, reductions in the amount of stock, provisions for the better distribution of stock by the regulation of watering places, and the exclusion of sheep from cut-over areas on which reproduction is deficient until the seedlings reach a sufficient height to be out of the reach of the animals.

Protection from Insects and Diseases. In coöperation with the Bureau of Entomology and the Bureau of Plant Industry the Forest Service is conducting a large number of studies and investigations dealing with the insects and diseases that do destructive damage to forests. The direct result of these studies will be the gradual eradication of predaceous insects and dangerous tree diseases from the valuable timber forests of the Government. Control measures already taken have shown the value of exact scientific information. On the Klamath National Forest some years ago about 900 acres were treated for insect infestation. The cost was about $3,000 and the amount of timber saved by the eradication of the insects was worth over $600,000. Other studies are carried on to identify and describe certain classes of insects, such, for instance, as those that destroy the seeds of trees in the cones. The various families, genera, and species of forest insects are studied and described, and the results are published in the form of monographs. Many of these insects are difficult to identify and concerning others very little is known. Investigations on tree diseases have not made such good progress, because tree diseases are much more difficult to control. Tree diseases, like human diseases, must be prevented instead of controlled. A general survey of the tree diseases prevalent in the National Forests has been made, especially in California. Further studies have brought to light little known or even unknown diseases. In California, studies have shown that a certain relation exists between old age and disease. Incense cedar, for example, seems to become infested after it reaches maturity at an age of about 150 years.

Tree Studies. Commercial tree studies are made of important tree species. The results are published in the form of monographs dealing with the range, silvicultural characteristics, growth, yield and management of each tree. These studies bring together all the important facts known about the tree described, such as: the industrial uses of the wood, the conditions under which the tree succeeds, the rate of growth in different situations, and the most suitable methods of management to secure the highest returns. Tables are included to show the volume of the trees at different ages and sizes, in cubic feet, in cords, in board feet, etc. Studies are also made of the life history and requirements of important forest trees, often in connection with commercial studies. Such studies cover: local, geographical, and commercial occurrence of the species, the species which are associated with it, the habit of the tree, its soil and climatic requirements for germination and growth, and the various matters connected with its reproduction. Such publications as these give the Forest officers much valuable information about the trees with which they are dealing, and also furnish the only sources of information to students in forest schools on the characteristics and requirements of the trees important in forestry in this country.

Grazing Investigations. Grazing investigations, being intimately connected with a great national industry, have received a considerable amount of attention. These studies are confined at present to grazing reconnoissance, the reseeding of depleted mountain grazing lands, studies in the best methods of handling sheep on the range, studies of the effect of grazing on the forest, identification of range plants, and the systematic elimination of poisonous range plants and predatory animals.

Grazing reconnoissance is a stock taking of the forage possibilities of a certain piece of range land. This work is usually done by organized parties, but a small amount is done also by Forest officers in spare time. This study aims to collect all the important grazing information, such as: the area of grazing lands, the kind of forage, the species of forage plants, the location of streams, springs, and other watering places for stock, the location of stock driveways, drift fences, and cabins, the location of timber lands that do and those that do not contain forage, and many other matters pertaining to the grazing of stock. The maps and field data secured furnish the basis for range improvement and more intensive range management. Up to date, over 12,288,885 acres of range lands have been covered in this way.

All intensive forage and range experiments are conducted at the Great Basin Experiment Station on the Manti National Forest. Here intensive problems are carried on under controlled conditions and under constant and careful observation and the necessary care and thoroughness is given to them which could only be given them at a fully equipped experiment station. All grazing investigations on the National Forests are carried on under the direct supervision of this station.

The seeding of depleted grazing lands is accomplished either by direct artificial seeding or through rotation grazing. Under the former method the seed of native or foreign grasses and other range plants are sown on the range, in the attempt to increase the forage crop. By rotation grazing, that is, permitting the stock to feed first on one area and then on another, the grasses and forage plants are allowed to recuperate from the effect of grazing and allowed to reproduce. The stock is excluded from one area while the seed is maturing, and after the seed has matured and become scattered on the area the stock is allowed to graze on it. As the stock feeds on the plants it tramples the seed into the ground and thereby furnishes favorable conditions for the germination of the seed. There are few parts of the National Forests that cannot be completely regenerated by the adoption of either one or the other of these two methods.

To reduce interference with the natural processes of reforestation, damage to tree growth and watersheds, depletion of grazing lands, and the waste of valuable forest resources, it is important to develop improved methods of managing different kinds of live stock on different types of land. These new methods of handling stock have been applied only to sheep. The lambing of sheep in small inclosures on the open range has resulted in the saving of a large percentage of the lambs. The new method of bedding sheep where they happen to be at nightfall has been found to have many advantages over the old system of returning them to an established bedding ground a number of nights in succession. The results have been better sheep, less damage to range, and more feed.

It was not so many years ago that practically nothing was known about the various plants which make up the forage crop on the National Forests. Forest officers could not identify the plants or say whether they were of value for forage or not. This made it difficult to secure the use of each range by the class of stock to which it was best adapted, to apply deferred and rotation grazing and to eliminate losses from poisonous plants. This obstacle to efficient range management was overcome when a system of plant collection and identification was started by the Forest Service. Some 23,000 specimens of about 3,000 different species have been collected on the National Forests, identified by specialists and the collector informed as to the value of each species. The identification of range plants is the first step toward securing an intimate knowledge of the life history of the plant. Such information as the soil and moisture requirements, date of flowering and seeding, requirements for reproduction, and its relation to other range plants is of the utmost importance if the maximum forage crop is to be produced on the range each year. This constitutes the latest stage in the development of grazing studies.