UNITED STATES DEPARTMENT OF AGRICULTURE 



DEPARTMENT BULLETIN NO. 1231 



Washington, D. C. W June 26, .1924 



TESTS OF METHODS OF PROTECTING WOODS AGAINST TERMITES OR 



WHITE ANTS. 



A PROGRESS REPORT. 



By Thomas E. Snydeh, Entomologist, Forest Insect Investigations, Bureau of 



Entomology. 



CONTENTS. 



Page. 



Introduction 1 



Description of experiments 2 



Treatments for timber to be set in 



the ground 9 



Superficial treatments 9 



Impregnation treatments 10 



Other treatments 12 



Page, 



Treatments for wood products not to 

 be set in contact with the ground 



or in wet situations 12 



Termite-resistant woods 14 



Poisons for wood-pulp products 15 



Summary 16 



INTRODUCTION. 



Insects cause very large annual losses of forest products. A con- 

 servative estimate of loss, placed at but 2 per cent of the value of 

 the yearly cut of forest products. 1 represents $45,000,000 annually. 

 While much of the loss in both crude and finished forest products 

 can be prevented by proper management, based on a knowledge of 

 the life histories of the insects, nevertheless special preservative treat- 

 ments are necessary to protect crude manufactured utilized products, 

 such as lumber, dimension timbers (PL I, fig. 1), telephone and tele- 

 graph poles, mine props, and posts (PL I, fig. 6) as well as the more 

 finished products, namelv, interior woodwork (PL II, fig. 6), furni- 

 ture (PL I, fig. 3; PL II, fig. 5), cabinet woods (PL II, figs. 1, 2), etc. 



Saving forest products will help save our national forests. The 

 various degrees of skilled labor, treatment handling, and change in 

 ownership consequent in the transformation of forest trees into prod- 

 ucts greatly increases their value. Hence, wood preservation is of 

 vital importance in the national program of forest conservation. 



Termites or " white ants " are the insects which are especially 



destructive to untreated wood in any form, in both this country and 



/the Tropics. Indeed, a large market for both crude and finished 



1 U. S. Dept. of Agriculture, Yearbook 1922, page 172. 

 71723°— 24 



