8 BULLETIN 1231, U. S. DEPARTMENT OF AGRICULTURE. 
with Oil A, No. 2. Stakes under these treatments were numbered 
from 109 to 193, and received the treatments shown in Table 3. 
TABLE 3.—Oils and processes used in impregnating Stakes 109 to 193. 
| 
Oil A. Oil B. Wood creosote. 
fe) 
al} 
> 
| | 
Full-cell. | Rueping. | Full-cell. | Rueping. | Full-cell. 
Rueping. | Special. 
; 
Stake. | Stake. Stake. Stake. Stake. Stake. | Stake 
WY a abs tobi 112 115 110 134 109 
118 169 113 119 131 150 114 
121 171 126 120 132 151 122 
123 172 127 124 133 152 148 
125 173 128 116 147 156 174 | 
144 177 130 138 153 157 175. | 
149 178 135 139 155 158 ie 
176 179 136 140 167 159 133 | 
182 180 137 142 170 160 186 
187 184 143 146 190 162 189 | 
188 185 145 161 192 168 7.413 ee | 
111 191 166 164 193 165 99a ee 
Treatment marked “ Special” treated with oi] to refusal. 
Stakes 129, 141, and 154 were missing. 
With these treated stakes were placed 22 untreated check stakes. 
(See fig. 2 for arrangement of stakes.) 
Other treated stakes have since been added to this test at irregular 
intervals. 
Coal-tar creosote oils containing varying percentages (high and 
low) of naphthalene and tar acids were included in the test treat- 
ments, since it was formerly considered that a high percentage of 
naphthalene in coal-tar creosote oils was more effective against marine 
borers and that a high percentage of tar acids was more effective as an 
antiseptic in preventing fungous decay. 
Some of the objections to coal-tar creosote as a wood preservative 
are disccloration, odor, and smarting to eyes and touch, “ sweating” 
in hot climates, soiling clothes, and corroding rubber insulation; 
that is, when conduits are impregnated with creosote, the creosote is 
said to be injurious to the rubber insulation on cables. Wood treated 
with creosote can not be painted or finished after treatment. 
Many of the objections can be avoided by proper treatment and 
regulating the amount of creosote held in the wood by the “ empty- 
cell” or “ open-tank” impregnation treatments. Impregnation with 
coal-tar creosote is by far the most effective treatment for timber to 
be placed in or in contact with the ground. Attack by termites to 
a telephone pole line in Vir ginia is very slight (usually through 
season checks), after 25 years’ service. By adding pigment to creo- 
sote, as is done in the preservative treatment given shingles, a painted 
effect can be obtained which does away with the brown discoler ation, 
DESCRIPTION OF PLATE I. 
EXPERIMENTAL WORK WITH WoOOD PRESERVATIVES AND DAMAGB TO RESISTANT REDWOOD 
AND WoopworK IN BUILDINGS BY TERMITBS: 1, Section of woodwork in building 
damaged by Cryptotermes brevis at San Jose, Costa Rica. 2, An ineffective method of 
wood treatment. Experimental ash block steamed 10 hours at 28 pounds pressure, after 
6 months’ tests buried in the ground with logs infested by Reticulitermes in Virginia. 
8, Rocker of. rocking chair damaged by (©. brevis, Key West, Fla. 4, Homemade, crude 
“open tank” plant at eastern field station, Falls Church, Va. 5, View of a portion of 
the treated experimental stakes at Falls Church, Va.. March, 1917. 6, One of several 
fence posts of redwood (Sequoia sempervirens) (heartwood) damaged by the termite 
Reticulitermes humilis var. hoferit from Sabino Canyon, Santa Catalina Mountains, Ariz. 
