under the hark, by submerging in water. Once they are established in the 

 sapwood, it is more difficult to. kill them. 



Prevention 



The most practical way of protecting green ash logs and lumber from 

 insect injury is to make such changes in the methods of management in the 

 woods and in the storage of logs at the mill or in the lumber yard as are 

 necessary to produce conditions unfavorable for these insects. Such pro- 

 cedure is necessary since they are active nearly the entire year. Ambrosia 

 beetles are active in both the Delta section of the Mississippi Biver and 

 in the South Atlantic States from February 15 to iSfcvember 15, causing most 

 serious damage during warm, damp days of the summer. Occasionally they 

 will appear during mild days of an open winter. Adults of the wormhole 

 borers are more or less active during the entire summer. In the Delta 

 section the beetles have two main flight periods (February 15 to March 15; 

 May 15 to June 15) and a partial third (August 15 to November 15) each 

 year. In the South Atlantic States, along the Savannah and Altamaha Rivers, 

 the period of activity is somewhat shortened (April 1 to October 15). 



Protection of green logs when prepared for float ing . 

 For logs near the water . - 



(1) Cut the timber at any time of the year provided the logs are 

 in the water one month after f el ling . 



(2) Prevent logs from being left on the ground during the flight 

 periods of the insects. 



(3) Avoid leaving logs in the woods in low, damp, shaded places. 

 When not possible to remove them at once, pull to higher places and cut 

 the surrounding shrubs and trees which produce excessive shade. (Such a 

 procedure will aid rapid seasoning and make the logs less attractive to 

 pinho le borer s . ) 



(U) Logs that must be left on the river bank for several weeks be- 

 fore rafting should be placed on saplings on the ground to expedite drying 

 by the free circulation of air and sunshine. 



(5) Dogs cut in the Delta section between October 15 and February 

 15 may be left in the woods until March 15, provided the above precautions 

 (2 and 3) are taken. This period in the South Atlantic States may be ex- 

 tended to May 1. 



(6) When rafts are made of green timber, and shoots grow so as 

 to shade the logs, the growth should be removed. 



(7) Keep the rafts in the sun as much as possible. 



