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 " heatino; 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.^^ 



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 und^r 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 man}^ 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 



1* National Implement and Vehicle Association and other Vehicle and Vehicle Parts 

 Manufacturers. Information Division of the Wa^on and Vehicle Committee and the 

 Wheel Manufacturers' War Service Committee. Wood Stock Committee. Sap-sitain and 

 mold in transit. Nat. Implement and Vehicle Assoc, etc., Bui. 30, 5 p. 1918. A. B. 

 Thielens, chairman. Typewritten. 



