SAP-STAIN, MOLD, AND DECAY IN GREEN WOOD. 21 
tion after one or two months on the road. Losses in those cases were 
often practically complete. Sixteen different firms reported that 
for the year 1917 their individual losses due to " heating in transit,'' 
as staining is sometimes explained by lumbermen, varied from $100 
to $5,000. One company reported the losses as varying from $25,000 
to over $75,000 in different years. 14 
CONTROL MEASURES. 
A great many attempts have been made to devise measures for 
the control of sap-stain and mold in green timber. With the excep- 
tion of kiln drying, however, none of these has proved entirely satis- 
factory. When tried under circumstances unfavorable to the growth 
of fungi, some of these measures have met with considerable success, 
but when put to the test under conditions which stimulate fungous 
development, they have often failed. For the most part, they have 
been prophylactic rather than curative in nature. However, it is 
believed that many of the following measures, although not entirely 
effective, will assist materially in reducing losses due to sap-stain, 
mold, and incipient decay in green stock. 
HANDLING IN THE WOODS. 
AUTUMN AND WINTER CUTTING. 
Many lumbermen (15) think that, where possible, timber should be 
cut in the autumn and winter. While this is probably true, the reason 
often given is incorrect. The statement is usually made that winter 
cutting is better because the " sap is down." It has been shown by T. 
Hartig (33, tables; Janka, 26) that during the spring when the growth 
is most active the tree sometimes contains less water than in the winter. 
It is probable that the changes in moisture content which do take place 
are confined mainly to the sapwood. It is true that the movement of 
sap is much more rapid at the time of active growth and that there 
are important chemical changes which take place therein during the 
different seasons of the year. In the winter, insoluble starches and 
gums are stored in the sapwood. During the spring these are 
changed to soluble sugars and are borne through the living tissues. 
The sapwood of summer-cut logs, therefore, contains soluble foods 
which render it extremely susceptible to attacks by fungi during the 
warm months when these organisms are most active. Winter-cut logs, 
on the other hand, have an opportunity to season under conditions 
less favorable for fungous growth and by the time warm weather 
14 National Implement and Vehicle Association and other Vehicle and Vehicle Parts 
Manufacturers. Information Division of the Wagon and Vehicle Committee and the 
Wheel Manufacturers' War Service Committee. Wood Stock Committee. Sap-stain and 
mold in transit. Nat. Implement and Vehicle Assoc, etc., Bui. 30, 5 p. 1918. A. B. 
Thielens, chairman. Typewritten. 
