-June 7, 1924 
Temperatures Fatal to Powder-Post Beetle 
1037 
LOT III 
Lot III was placed in the kiln at 8.30 a. m., December 14, at a temperature of 
90° F., which was raised to the initial point, 120° F., by 9 a. m., and held there 
one-half hour. Pieces were removed at 10° intervals up to 160° F. Samples 
were taken out at 120° and 160° F., as well as at the intermediate intervals, 
because samples in Lots I and II subjected to these temperatures apparently did 
not contain any active larvae. It was decided to make removals every half hour 
to determine when the larvae ceased to be active. The first two removals at 120° 
and 130° F. probably did not allow the samples to remain in the kiln long enough 
for all parts of the wood to reach the kiln temperature. The maximum ther¬ 
mometer indicated that the recording thermometer read 5° too low at 120° F., 
2° too low at 130° F., 3° too low at 140° F., 2° too low at 150° F., and 1° too low 
•at 160° F. 
Table III. — Experiments to determine temperatures fatal to Lyctus planlcollis by 
steaming infested ash lumber in a kiln . Lot III 
Sam¬ 
ple 
No. 
j 
Size 
Tempera¬ 
ture and 
time held 
Time 
held at 
accumu¬ 
lated tern 
perature 
starting 
at 130° 
F. 
Humid¬ 
ity 
Propor¬ 
tion of 
sap- 
wood 
Num¬ 
ber of 
piles of 
frass 
noted 
before 
steam¬ 
ing 
Larvae 
chopped out 
immediately 
after steam¬ 
ing-number 
and condition 
1 ~ 
Final examination, 
Jan. 10, 4 weeks 
after steaming. 
Piles of frass 
noted; larvae 
chopped out 
where results 
were doubtful ® 
! 
Inches. 
°F. 
H 0 UT 8 
Hours. 
Percent. 
Percent. 
1 
2X12X18 
160 
4 
24 
100 
20 
3 
No signs ofactiv- 
itv. 
2 
2X12X18 
160 
4 
2% 
100 
85 
G) 
Do. 
■3 
2X12X18 
160 
4 
24 
100 
15 
1 
i Do. 
4 
2X12X18 
160 
4 
24 
100 
20 
3 
!--- 
! Do. 
■5 
2X12X18 
150 
4 
2 
100 
15 
G) 
: Do. 
6 
2X12X18 
150 
2 
100 
15 
3 
Do. 
7 
2X12X18 
150 
2 
100 
15 
2 
! Do. 
8 
2X12X18 
150 
2 
100 
15 
2 
Do. 
9 
! 2X12X18 
140 
4 
14 
100 
25 
G) 
Do. 
10 
2X12X18 
140 
4 
14 
100 
15 
G) 
— 
2 piles of frass noted 
Dec. 21 .a 
11 
2X12X18 
140 
4 
14 
100 
20 
2 
No piles of frass 
noted Dec. 21; 6 
on Jan. 10.® 
12 
2X12X18 
140 
4 
14 
100 
15 
G) 
No signs of activ¬ 
ity. 
13 
2X12X18 
130 
4 
1 
100 
15 
G) 
Do. 
14 
2X12X18 
130 
4 
1 
100 
10 
G) 
4 piles of frass noted 
Jan. 3.® 
15 
2X12X18 
130 
I 
1 
100 
20 
2 
5 piles of frass noted 
Jan. 3.® 
16 
2X12X18 
130 
X 
1 
100 
20 
G) 
Clerid larva 
alive; white 
Lyctus. 
36 piles of frass 
noted Dec. 15.® 
17 
2X12X18 
120 
4 
4 
100 
20 
G)- 
17 piles of frass 
noted Dec. 17.® 
18 
2X12X18 
120 
4 
* 
100 
20 
(*) 
_ _ 
2 piles of frass 
noted Dec 21 .a 
19 
2X12X18 
120 
i 
4 
4 
100 
25 
1 
' ' "" 
11 piles of frass 
noted Dec. 15.® 
20 
2X12X18 
120 ! 
I 
4 
4 
100 
95 
10 
2 Lyctus, 1 
clerid alive. 
34 piles of frass 
noted Dec. 15.® 
21 
1X12X18 
160 
4 
24 
100 
100 
5 
No signs of activ¬ 
ity. 
22 
1X12X18 
160 I 
4 
24 
100 
15 
G) 
Do. 
23 
1X12X18 
150 j 
* 
2 
100 
25 
4 
Do. 
24 
1X12X18 
150 ! 
4 
X 
2 
100 
20 
1 
Do. 
25 
1X12X18 
140 ! 
14 
100 
15 
G) 
1 
Do. 
26 
1X12X18 
140 ; 
4 
14 
100 
15 
( b ) 
Do. 
27 
1X12X18 
130 | 
4 
1 
100 
15 
G) 
Do. 
28 | 
1X12X18 
130 | 
* 
1 
100 
15 
G) 
Do. 
29 
1X12X18 
120 ! 
i 
1 
i 
* 
100 
5 
G) 
4 piles of frass 
noted Dec. 29.® 
a Reported by C. C. Shackford and checked on final examination by R. A. St. George. 
6 No piles of frass noted, but all samples infested. 
96461—24f-5 
