72 THE NATIONAL FOEEST MANUAL. 



The supervisor should see that the notice warning the public of this regula- 

 tion is posted at the entrances to the Forests and at all camping grounds and 

 at other suitable places. 



When a Forest officer discovers insanitary conditions he will first request the 

 trespasser to comply with the regulation, and if the trespasser refuses will 

 take the necessary action to remove the nuisance and then follow the usual 

 procedure for trespass cases. 



FOREST PRODUCTS. 



ORGANIZATION. . 



The aim of the Branch of Products is to promote the economical production 

 and use of all forms of forest products. The work consists of investigations of 

 physical, mechanical, and chemical properties of various species of wood, of 

 conditions affecting these properties and the use of the woods in various indus- 

 tries, and of fundamental principles underlying various processes and methods 

 of utilization. It includes also statistical studies relating to the production, 

 value, and uses of various woods. 



The work is centered at the Forest Products Laboratory, Madison, Wis. The 

 direction of the laboratory is the administrative head of the branch and is 

 responsible to the Forester for the technical methods used in all work and for 

 the executive supervision of work conducted outside of the National Forest 

 districts. Other offices of products are maintained in Districts 2, 5, and 6, and 

 in Washington, D. C. When products work is required in District 1 or in 

 Districts 3 and 4, the District Forester concerned will take the matter up with 

 the director of the Forest Products Laboratory, who, upon approval of the 

 proposed work, will make the necessary arrangements. In cases where a man 

 is detailed for work in any of these districts he will report directly to the 

 District Forester. All correspondence from the districts will be addressed to 

 the director. 



CHARACTER OF "WORK. 



Work conducted by the branch is along the following general lines : 

 MECHANICAL AND PHYSICAL PROPERTIES AND STRUCTURE OF WOODS. 



Mechanical properties. The tests of mechanical properties are primarily for 

 the purpose of accumulating reliable information on the strength of various 

 species and forms of timber. The results are of value to engineers, manufac- 

 turers, and other users of wood in enabling them to employ the various species 

 and forms most advantageously, and frequently to substitute less well-known 

 species for those which have been commonly used but are becoming scarce. 



The work covers tests on small specimens to determine the properties of the 

 clear wood, tests on structural sizes containing the defects ordinarily found in 

 such timbers, tests on manufactured articles, and tests to determine the effect 

 of preservatives, preservative treatments, and other commercial processes on 

 the strength of woods. 



Physical properties. A knowledge of the physical properties of wood in gen- 

 eral and of the various species individually is essential to the most efficient 

 utilization of the material Not only is such knowledge of importance in con- 

 nection with the studies of structural and mechanical properties, but it is 

 especially necessary for successfully conducting the investigations relating to 

 wood preservation and other wood-using industries. The investigations cover 

 studies of the fundamental physical properties, such as thermal properties, 

 penetrability to liquids and gases, hydroscopicity and density; they include 

 also experiments in air-seasoning, kiln-drying, and transformation of wood. 



Relation of structure to properties. The microscopic structure of wood is 

 very closely related to its physical and mechanical properties and uses. A de- 

 tailed study of the structure of various commercial species will be made, the 

 results of which will be valuable in indicating the uses to which the species 

 are best adapted and will assist in the determination of other properties and 

 of the behavior of the woods under various treatments. 



WOOD PRESERVATION. 



The study of wood preservation deals with the protection or preservation of 

 wood from decay, fire, insects, and other destructive agencies. Of these, decay 



