Because plants of this character are usually located in rather remote places, the larger estab lishments usually include housing facilities for employees, fire protection equipment, a com missary store doing a general merchandise busi ness and often an electric-light plant. In many instances, also, schools, churches and other pub lic buildings are provided and maintained by the operators.
Where a mill is located on tidewater, it usually has dock and loading facilities for shipping its product to market by water, and thereby enjoys the advantage of low water freights. The great majority of the mills, how ever, are dependent on the railroads for their shipping facilities and their markets are usually restricted to some extent by freight rates which make unduly long hauls prohibitive. Thus, the Douglas fir producers of the North Pacific coast are able to ship the large structural tim bers which can be turned out of giant fir logs to all parts of the United States because they have no competition for this trade, but the common building lumber made by these same mills cannot be shipped by rail to the eastern part of the United States because the freight is so high that yellow pine from the Southern States can be sold at lower prices.
Grading and Inspection of Lumber.— Lumber is graded according to its strength, durability and, in the case of material for cer tain uses, its external blemishes. Thus, in the case of a piece that will be used as a beam or joist, the appearance of the piece is of little consequence, but its strength is highly important and if it is to be used in a position where it will he exposed to moisture and heat the ques tion of durability under such exposure becomes equally important. But in the case of a piece of oak that is to be used for a drawer front or a table top, strength is of less consequence than a clear surface.
The commonest of all the defects found in lumber is the knot, and it is apt to impair the grade and value of the piece in which it is found regardless of the use to which the mate rial is to be put, since it affects both strength and appearance. A large knot in a partly rotten pocket may reduce the strength of the piece to the minimum, while a small tight knot may have little effect, as far as strength is concerned, but will deface the surface of the piece to such an extent that it cannot be used for an exposed part in a piece of fine furniture.
Other important and common defects that affect the grading and value of lumber are checks, splits, pockets of foreign material, such as pitch in pine or sand in some hardwoods; various kinds, of stain or discoloration; wind shake, which is a product of strains set up in the fibre of the wood when the tree is bent by heavy winds and takes the form of splits; sapwood in a piece that is intended to be used where heartwood is specified; various kinds of rot and fungus decay, such as "red hearts in yellow pine and speck" in cypress; "waney" or bark edges; warpage and twisting that affect the usefulness of the material; wormholes and like products of insect blights; discoloration from age and exposure, etc.
Each of the principal commercial woods is graded by fixed rules that establish certain grades and define the limits of each grade. These rules are made and maintained by asso ciations of lumber manufacturers—also in cluding in a few cases the wholesale distributors —and are usually enforced by means of an inspection force whose function is to settle dis putes regarding grades and to make certain that the lumber inspectors employed at each mill are accurately and fairly interpreting the grades, as the lumber is sorted and marked when it comes from the mill. The associations maintaining grading rules and inspection serv ice include Northern Pine Manufacturers' Association, Minneapolis, Minn. (white and Norway pine) ; Southern Pine Association, New Orleans, La. (southern yellow pine) ; North Carolina Pine Association, Norfolk, Va. (short leaf and loblolly pine from Virginia and North and South Carolina sold under the trade name "North Carolina pine") ; West Coast Lumber men's Association, Seattle, Wash. (Douglas fir, western spruce, cedar and hemlock) ; Western Pine Manufacturers' Association, Spokane, Wash. (western white and yellow pine, larch) ; Southern Cypress Manufacturers' Association, New Orleans, La. (southern cypress); National Hardwood Lumbermen's Association, Chicago, Ill. (all hardwoods). Each of these organiza tions has established its grading and inspection service as standard for the particular wood or woods covered.