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perhaps double the above estimate. Such waste and degrade, if prevented, would mean better stock for the purchaser and bigger profits for the operator. The salvaging of this material would ultimately mean a direct saving of stumpage. It is quite possible that a concern planning on a 10-year supply of logs from its timberlands under the wasteful method would be able to extend this to a 12 or 14 year cut under the less wasteful one. The amount of stumpage saved each year by this means would soon show an appreciable reduction of the annual drain on our forest resources.

Logs and trees left in the woods following logging, insect-control work, and similar activities, and following fire and windfall damage, deteriorate rapidly. The data collected by Boyce 34 on western yellow

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FIGURE 22.-Red gum logs heavily sap stained during storage in the mill yard. Considerable sap rot has already developed in these logs and many of the boards cut from them will contain some of the infection

pire insect-control projects show that the felled and barked trees lying on or near the ground were completely sap stained by the end of the first season of exposure. Rapid decay of the sapwood, with a slower rate of decay for the heartwood, takes place the first season, and by the end of the second season the volume of the merchantable wood in the felled trees had been so greatly reduced by decay that the salvaging of the logs had become uneconomical.

It is unquestionably true that in better methods of handling and storing logs is to be found the solution to this particular waste prob

34 Boyce, J. S., Deterioration of Felled Western Yellow Pine on Insect-Control Projects: U. S Dept. of Agri. Bul. 1140: 1-7; 1923,

lem. But, unfortunately, this is only half the story, for the sap stains and sap rots which enter the freshly cut or the stored log often continue their development in the boards placed in the piles for air-seasoning. This accounts for much of the heavy bluing and rotting of air-seasoned sap gum and for the well-known "interior dote" of elm and other hardwoods. Furthermore, small checks starting in the log during storage become closed when the logs are soaked or kept in the pond and may enlarge during the seasoning of the lumber. It also often happens that boards cut from infested logs contain insects or insect larvæ which may seriously damage the stock unless they are killed by heat or chemical treatment. To complete the story, then, we must add to the log storage the losses due to the deterioration of lumber cut from insect or fungous-infected logs.

The

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FIGURE 23. The yard of a large hardwood plant showing long piles of stored hardwood logs, track facilities, and steam loader. Many of these logs when sawed showed from 1 to 3 feet of the ends badly decayed and in some piles the loss due to decay represented 25 per cent of the log volume

prevention of losses in this type of lumber is essentially a seasoning problem. However, these seasoning losses and the losses occurring in log handling and storage can be greatly reduced by improved practices.

LOSSES IN AIR-SEASONING, STORAGE, AND TRANSIT

It is often difficult to understand just how degrade due to sap stain constitutes a loss, and many millmen and manufacturers will say that there is no loss in blued stock because it is eventually sold as lower-grade material. But right here is where the loss occurs, for sap stain develops in otherwise high-grade stock, and the reduction in quality represents a loss in value which is chargeable directly to sap stain. It is not a total loss comparable to a loss by fire; it is a depreciation loss, for blued stock never entirely loses its usefulness

unless decay has developed.35 It is found that the influence of this loss is far-reaching and has a definite bearing on the overcut of the standing timber in regions where the demand for high-grade material results in excessive cutting and therefore in the accumulation of much low-grade sap-stained stock.

The first loss due to blue stain is in the reduction in grade as the board sawed from a blued log passes over the grading chains. Whether the stock is subsequently kiln-dried or air-seasoned, blue stain at this stage may affect the grade appreciably. Very often blue stain develops in the log and is carried over in the board, acting as a source of infection to the neighboring unstained boards in the same pile.

The next lowering of grade takes place when blue stain develops in the sap boards piled in the yard for air-seasoning. Considerable loss at this stage is found in lumber sold in the rough, unplaned.

Where the blue stain is superficial in lumber which is planed, very often the planing removes the darker stain and mold growth and the product suffers little, but in deeply stained stock the surfacing process does not remove the blemish. Following this, if the stock is stored improperly or shipped under unfavorable conditions, blue stain may again develop and take its toll through degrade. This loss in shipment may occur in rough stock as well as planed stock.

A fourth form of loss occurs in the degrade of the finished product. In such industries as the sash, door, and millwork, the lumber purchased is already graded and the blue stain present in such stock has been accounted for and the degrade applied. When this blued wood is used in the finished product of these mills the sap stain is again responsible for a reduction in the selling price of the product. This reduction in price for blued stock averages 25 per cent in a certain sash, door, and millwork association. It is thus seen that the loss due to sap stain may often occur in the various steps of manufacture, in transportation, or in storage. A pine board may be reduced in grade on the sorting chains on account of stain, it may then go to the airseasoning pile and suffer further loss, or it may be kiln-dried and, due to subsequent improper storage, further staining may lower the grade. Eventually one of these blued boards may again cause loss in the finished product on account of the blemish. Unlike decay, blue stain rarely causes a total loss of the product.

Another source of loss is represented in the use of molded barrel, box, basket, or other stock in containers used for shipping fresh and perishable food products. The presence of the mold spores in large quantities adjacent to perishable food products may easily cause rapid decay or contamination of the food products and thus result in serious losses. An instance may be cited where moldy basswood box boards were used in the manufacture of containers for shipping butter. The mold, under favorable conditions, contaminated the butter in these boxes and so caused a heavy loss. Fruits and vegetables may become contaminated in a similar manner.

The veneer industry uses the best grade of logs, 16 inches at the small end, and without defects, and this calls for the cutting of the

5 Hubert. E. E., The Utilization of Blue-Stained Wood: Sash-Door Finish. 4:17. September, 1922; Hardwood Record, Oct. 25, 1922. Also see Forest Products Laboratory Technical Note No. 184.

finest trees in the virgin stands. In red gum, for example, the heartwood may be used for veneer or for lumber. In either case the demand for the heartwood is often greater than for the sapwood products, and the sap gum stock accumulates. During the short period of air seasoning this accumulated stock deteriorates rapidly through sap stain.

It is unquestionably true in a great many instances that what amounts to an overproduction of the lower grades of lumber and other wood products may be traced to the discoloration of sapwood by fungi. A very large amount of timber must be cut in order to produce a large amount of upper-grade stock free of stain, and this alone results in the accumulation of the less desirable lower-grade stock. Species with a large percentage of sapwood are foremost on this list. At one of the western mills cutting western yellow pine as much as 75 per cent of the air-seasoned selects and shop-grade stock is reduced in grade, due to sap stain developing during the less favorable months. In this way sap stain increases the total of lower-grade stock by reducing the amount of upper-grade material. To the bluing of sapwood, therefore, may be laid indirectly a considerable part of the annual cut, which could otherwise be reserved for future

use.

In a study of the sap-stain problem it is found that these losses are not confined to the United States but are world-wide, occurring wherever trees are cut for lumber. For instance, Wilson,36 writing on the bluing of coniferous timber, estimates that in Germany the value of timber affected by blue stain is diminished from 25 to 50 per cent; in Sweden the depreciation in value of blued timber is 14 per cent; in Great Britain blued wood is priced considerably lower than bright stock, and for many uses blued wood is not accepted at all; and in Russia the damage due to blue stain is considered very serious, principally on account of transportation difficulties which delay the cutting of the logs into timber.

The general attitude of the lumber trade of many foreign countries toward sap-stained material is expressed in the specifications for stock exported from the United States. In this country the most rigid demands for bright sapwood are found in the orders for export stock. In 1922 "bright" sap gum sold for from $2.50 to $5 and on up to $15 per thousand board feet above the price paid for blued stock. Southern yellow pine without sap stain brought from $10 to $27 more per thousand board feet than blued stock. In general, the demand is for bright stock, and better prices are paid for this grade. The fact that decay often develops in blued sapwood has perhaps some bearing on the demand for species which the purchaser by experience finds consistently infected with sap stain and "dote."

SAP-STAIN LOSSES

A survey of the principal wood-producing and wood-using industries of the country was begun in 1921 in an effort to obtain loss figures due to degrade on account of sap stain. A total of eight associations were asked to cooperate.

Wilson, M., The Bluing of Coniferous Timber: Trans. Roy. Scottish Arb. Soc. 36: 82-92; 1922.

Questionnaire reports were received with the assistance of the following: Southern Sash, Door, and Millwork Manufacturers Association; Southern Pine Association; Hardwood Manufacturers Institute; Associated Cooperage Industries; Northern Pine Manufacturers Association; Western Pine Manufacturers Association;

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FIGURE 24.-Hardwood logs in storage, showing the fruiting bodies of wood-rotting fungi developing from the decaying heartwood. These signs indicate that the rot in these logs may be extending and gradually reducing the volume of sound wood

California White and Sugar Pine Manufacturers Association; and the Northern Hemlock and Hardwood Manufacturers Association.

As a result of this excellent response, we have to-day more information than has ever before been available on the financial loss due to sap stain. In the reports received many of the mills stated that they suffered considerable loss due to blue stain but are unable

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