PROTECTING WOOCS AGAINST TERMITES. 9 



and the substance apparently dries more quickly. Tests have proved 

 that the addition of pigments, notably green, does not affect the re- 

 sistant qualities of the treated wood. 



The quantity of pigment (green) added to the creosote oils used 

 in the experiments was 1 pound of pigment to 1 gallon of creosote. 

 It is believed that satisfactory physical properties can be obtained 

 by reducing the amount of pigment, if the pleasing stain is not of 

 primary importance. The wood which was treated was yellow pine 

 and was more than half seasoned. Where the mixture was applied 

 by means of dipping, coal-tar creosote and pigment alone were used ; 

 but where creosote and pigment were applied with a brush the mix- 

 ture was slightly thinned with linseed oil, so as to encourage drying 

 and make the application easier. 



According to the Forest Products Laboratory, red and brown pig- 

 ments are less expensive than green; furthermore, a smaller amount 

 of red or brown pigment is necessary to obtain a satisfactorily col- 

 ored creosote than in the case of green. Red and brown pigments 

 can be used by the open-tank method or pressure method, whereas 



" % /3/ o //4 • /32 o /22 • /33 o /4B 



•21 



m - ,1 



9 no o ,09 • /3/ O //4 • /32 O /22 • /33 O Ma • / * 7 O /a6 • /92 

 "7 x /ea x //a x /«? x /z/ n/ x /23 x /72 x /ss x /7S /7a z&s 



9 //£ //& ^ //& /26 _ /20 /27 p /Z4 /28 <_ f/6 /45 ~ 



/34- /SO /S/ /52 156 /63 



q /S3 o *74- f&S o ,7S • * 7 O /ai • "° O /a3 • /9 ° O /as • /93 O 



V i*+V y. I/O y. I/O y. / /& y. /Oil X /OfJ y. /Of V 



■ T ■ 7 ■ ▼ ■ 



/35 ~ /39 /36 ~ /40 .'37 _ /42 /43 



/9/ 



/m i&^ /t?t? * /<w ;&/ * /^<£ /^c? ~ i*+o ioo ^ /of- 



/S7 /S3 /S9 /60 /6Z /65 



/fifev mO/LP.PULL CELL. + WOOD CPEOSOTE, PULL CELL. 



( ^t) ] O EMPTY CELL. 9 EMPTY CELL. 



mO/L B.EULL CELL. K SPEC/PL, OIL P. 



▼ EMPTY CELL . X SOME SPP WOOD. 



Fig. 2. — Arrangement of stakes treated bv the cylinder pressure process; at Falls 



Church,, Va. 



brushing or dipping must be used with green. The proportions are 

 8 to 12 ounces of pigment (ground in oil) mixed with an equal bulk 

 of linseed oil for each gallon of creosote. 



TREATMENTS FOR TIMBER TO BE SET IN THE GROUND. 



SUPERFICIAL TREATMENTS. 



The superficial brushing and dipping methods are temporarily 

 effective in preventing attack by insects to timber and crude forest 

 products ; results of tests and examinations of service test telephone 

 pole lines indicate that' the treated wood set in the ground usually 

 resists attack by wood-boring insects from 2 to 8 years, depending 

 upon the chemical, the thoroughness of the treatment, the character 



Description of Plate II. 



Resistant redwood damaged by native termites and other damage to wood by 

 termites : 1, Picture molding infested and ruined by Cryptotermes brevis in the old 

 Colonial Hotel, Nassau, N. P., Bahamas, 1921. View showing damage exposed. 2, Same, 

 showing how interior is eaten out, leaving hollow shell but with outer layers intact. 

 o, Permanent redwood stakes to support grapevines in Merced County, Calif., vineyards 

 damaged by the termite RetiouMt.erm.es hesperus, which also injures the young vines. 

 Side view. 4,, Same, edge view. 5, Bureau drawer injured by, the termite C. brevis, Key 

 West, Fla. 6, Oak flooring damaged By Reticulitermes in the eastern United States ; note 

 how damage is hidden (upper surface). 



