Table 5. Growth rates of southern pine beetle infestations before and after application of suppression treatments in 1996.

Pre-Treatment
Post-Treatment
Infestation
No.
Mean
DBH
inches
Trees
Killed/
Day
Active
Trees at
Treatment
Verbenone
used
ml/ft2
Trees
Killed/
Day1
%
Growth
Reduction
VERBENONE-ONLY
NC-01
 8.0
0.8
 40
40
0.3a
 63
NC-02
 7.5
0.6
 25
40.3
0.1a
 83
TX-01
 8.9
2.3
 49
40.1
0.0a
100
TX-02
21.4
1.9
 49
22.5
0.4a
 78
TX-03
 7.1
0.9
 45
50.2
0.2a
 80
TX-04
 8.4
0.7
 36
35.6
0.1a
 82
TX-05
 7.8
1.0
 28
54.1
0.1a
 88
TX-06
 6.1
2.3
101
51.9
0.2a
 89
TX-07
 14.2
0.6
 43
41.1
0.4c
 24
Mean
9.9
1.2
46.2
41.8
0.2
 76.32
VERBENONE-PLUS-FELLING
NC-03
 8.6
1.6
 59
23.8
0.5a
 69
NC-04
 80
1.3
 68
24.3
0.5a
 62
Mean
8.3
1.5
64
24.1
0.5
 65.52
UNTREATED CONTROL
NC-05
 11.2
-
 51
-
1.9
-
  1. a   Total suppression (no trees attacked beyond treated buffer during 6-week post-treatment period).
    b   Partial suppression (trees attacked beyond treated buffer, infestation growth decreased by > 50%).
    c   No suppression (trees attacked beyond treated buffer, infestation growth decreased by < 50%).


  2. Mean values were calculated by summing % reduction for each infestation and dividing by the number of infestations.