18 BULLETIN 1037, U. S. DEPARTMENT OF AGRICULTURE. 
LOSSES DUE TO SAP-STAIN OR MOLD. 
INSANITARY PRACTICES IN THE HANDLING OF GREEN WOOD STOCK. 
As a result of investigations in the woods, inspections of many car¬ 
loads of green timber and dimension stock upon arrival at the mill, 
examinations of green and seasoned manufactured stock upon ar¬ 
rival at the vehicle factory, and talks with practical millmen and 
lumbermen, the writer is convinced that a considerable amount of 
the damage to vehicle stock, due to fungi, is brought about through 
the use of infected raw material. Many of the infections take place 
in the woods, as a result of insanitary practices in the handling of 
logs, bolts, and split billets. In many instances, during warm and 
humid weather logs and bolts have been allowed to lie in the woods 
for weeks. Under such conditions sap-stain is almost certain to fol¬ 
low. Moreover, the liability to attack by wood-destroying fungi is 
greatly increased. 
Split billets, instead of being cross piled on dry foundations, are 
sometimes thrown carelessly about the stump and left until a con¬ 
venient time for hauling arrives. Under favorable circumstances it 
takes but a few days for certain fungi to gain a good hold on such 
stock, and unless later checked or destroyed by some process such as 
kiln drying, they may produce a permanent stain or decay in the 
sapwood. 
It is quite probable that a serious shortage pf cars suitable for 
handling the logs, bolts, and billets may prevent at times the rapid 
movement of raw stock to the mills. This results in the accumula¬ 
tion of material in the woods and railroad yards and contributes to 
conditions in many cases favorable to the development of the fungi. 
Frequently box cars are used where in normal times the more open 
and consequently better ventilated types of car would be employed. 
Failure to observe proper measures during storage, such as the 
use of dry foundations for logs and bolts, the cross piling or strip¬ 
ping of billets on dry foundations sufficiently high to give suitable 
ventilation from beneath, and the storage of stock in properly venti¬ 
lated sheds, has furnished conditions suitable for the development 
of mold, sap-stain, and decay in such material. 
A few millmen seem to have the mistaken idea that an abundant 
growth of mold on green stock serves to protect it from checking by 
preventing evaporation from the surface of the wood and actually 
absorbing, or possibly condensing, moisture from the surrounding 
atmosphere and then transmitting it to the wood. The fungus de¬ 
rives its moisture from the wood, not the air. Its presence, however, 
often indicates a high humidity in the immediate vicinity, a condition 
which prevents the drying of the wood and thus favors the growth 
of fungi. It is quite probable that the phenomenon known as gutta- 
