496 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol 14 



an infestation usually resulted in the bordering onion fields. One 

 field which bordered the railroad was practically free from thrips in 1919. 

 When the grower was asked about his practice as to this, he answered 

 that if the railroad company did not bum the grass in the fall and spring 

 he always made it his business to see that it took fire. The matter of 

 destruction, where possible, of places of hibernation is a phase of the 

 problem of control which has been neglected too often by the growers, 

 and yet it is one of the most powerful factors. Elimination of the sources 

 of infestation is far easier and more economical than checking the pest 

 after the outbreak begins. 



WHITE-ANT-PROOF WOOD FOR THE TROPICS 



By T. E. Snyder, Specialist in Forest Entomology, Bureau of Entomology, 

 U. S. Department of Agriculture 



It is well known that white ants or termites are extremely destructive 

 in the Tropics and that the woodwork of buildings and furniture must 

 be constructed either of woods naturally resistant to attack or of woods 

 chemically treated to prevent attack and rapid destruction. 



Foreign manufacturers advertise "ant-proof" furniture for South 

 American trade; American manufacturers have, as yet, not seriously 

 competed. 



Wood-pulp products, such as composition, ply and laminated wall 

 boards, m.anufactured in the United States, also demand chemical 

 treatment before they can be used in the Tropics. 



Rather discouraging to American manufacturers, is the fact that due 

 to spoiling the wood for fine finishing, cabinet woods can not be treated 

 by the usual effective chemicals. A solution is given in the use of ant- 

 proof woods imported from South America and other tropical countries 

 as veneers glued upon cores of cheap American woods chemically treated. 

 This well-known expedient is satisfactory, but there are other solutions 

 of the problem. 



A number of woods grown in the United States are very resistant to 

 attack by white ants. Hence, since many of these woods are suitable 

 for use as veneers, it is not necessary to import timber from the Tropics. 



Furthermore, there is a chemical treatment for cabinet woods that, 

 while it will somewhat darken the wood, if the wood is properly treated, 

 permits shellac or varnish to adhere, and a suitable finish can be ob- 

 tained. Wood treated with this chemical is both white-ant-resistant and 



