A classic
outbreak of second-generation true armyworm larvae developed in crops and lawns in the southern, central, and northwestern areas of the state this season. The earliest reports of armyworm activity began in mid-July, and the week of July 18 to 24 brought many armyworm sightings, most of which involved larvae migrating through residential yards to nearby crop fields. By July 31, reports of locally heavy larval populations had been received from Barron, Burnett, Chippewa, Clark, Columbia, Crawford, Dane, Dunn, Eau Claire, Green Lake, Iowa, Jackson, Jefferson, Monroe, Taylor, Vernon, and Washburn counties.
The timing of the infestations was characteristic of second-generation armyworms and was foreshadowed by large spring moth flights tracked by DATCP's True Armyworm Trap Network. Heavy migration flights in May laid the foundation for a second round of large, late June flights that produced the damaging larval populations in July. DATCP's 2025 true armyworm trap network captured a cumulative total of 14,488 moths in 53 traps (273 moths per trap average) April 1 to July 31. Peak spring moth flights were recorded the week of April 25 to May 1, while the summer flight peaked June 27 to July 3. Additional heavy flights in July signaled a potential for more larvae and feeding to extend into late summer, but the outbreak subsided by early August.
Moth Counts for the 2025 Season
Adams
|
Grand Marsh
|
| |
0
|
5
|
28
|
17
|
2
|
3
|
7
|
7
|
21
|
|
16
|
40
|
78
|
71
|
12
|
7
|
|---|
Brown
|
Greenleaf
| | |
2
|
28
|
23
|
71
|
47
|
46
|
16
|
8
|
104
|
521
|
255
|
361
|
144
|
14
|
12
|
15
|
|---|
Calumet
|
Kesler
| | | | |
1
|
1
|
2
|
7
|
6
|
7
|
26
|
13
| | 6
|
12*
|
| | |
|---|
Columbia
|
Cambria
|
0
|
0
|
0
|
20
|
31 |
46 |
4
|
4
|
4
|
0
|
3
|
15
|
5
|
5
|
13
|
15
|
5
|
1 |
|---|
Columbia
|
Columbus
|
0
|
0
|
0
|
1
|
2
|
2
|
2 |
1
|
0
|
0
|
0
|
0
|
1
|
1
|
0
|
0
|
0
|
0
|
|---|
Columbia
|
Lodi L
|
0 |
1
|
3
|
18
|
15 |
18
|
4
|
2
|
1
|
0
|
2
|
3
|
6
|
51
|
81
|
4
|
3
|
1
|
|---|
Columbia
|
Lodi M
|
4
|
4
|
12
|
6
|
5 |
5
|
6
|
2
|
0
|
0
|
0
|
0
|
9
|
1
|
0
|
0
|
0
|
0
|
|---|
Columbia
|
Pardeeville
|
0
|
0
|
0
|
21
|
45 |
12
|
1
|
1
|
0
|
1
|
1
|
3
|
1
|
0
|
1
|
0
|
0
| |
|---|
Columbia
|
Portage W
|
0
|
1
|
3
|
3
|
0
|
2
|
24
|
13
|
2
|
2 |
1
|
2
|
1
|
0
|
1
|
0
|
0
|
0
|
|---|
Dane
|
Deerfield
| | |
3
|
41
|
49
|
28
|
3
|
2
| |
5*
|
5
| | | |
|
| | |
|---|
Dane
|
Stoughton 1
|
0
|
0
|
24
|
138
|
276
|
4
|
13
|
7
|
27
|
2
|
9
|
|
|
| | | | |
|---|
Dane
|
Stoughton 2
|
0
|
0
|
8
|
29
|
27
|
30
|
1
|
3
|
1
|
1
|
8
| |
| | |
| | |
|---|
Dodge
|
Beaver Dam
|
0
|
1
|
10
|
20
|
73
|
35
|
6
|
14
|
13
|
21
|
3
|
9
|
1
|
155
|
3
|
1
| | |
|---|
Dodge
|
Leroy
|
0
|
0
|
4
|
21
|
14
|
50
|
9 |
3
|
0
|
0
|
0
|
1
|
0
|
|
0*
|
1
|
0
|
1
|
|---|
Dodge
|
Rubicon
|
0
|
0
|
1
|
3
|
8
|
4
|
0 |
2
|
0
|
3
|
1
|
24
|
13
|
38
|
3
|
5
|
3
|
2
|
|---|
Dodge
|
Waupun
|
0
|
0
|
7
|
142
|
153
|
51
|
37
|
14
|
19
|
38
|
3
|
17
|
1
|
200
|
42
|
7
|
9
|
3 |
|---|
Door
|
Sturgeon Bay
| | | | | | |
6
|
1
|
0
|
1
|
14
|
11
|
15
|
287
|
49
|
7
|
13
|
14 |
|---|
Fond du Lc
|
Johnsburg
|
0
|
0
|
0
|
16
|
45
|
31
|
39
|
40
|
23
|
39
|
115
|
180
|
|
35*
|
40
|
23
| | |
|---|
Grant
|
Lancaster 1 |
0
|
0
|
42
|
203
|
113
|
42
|
17
|
12
|
30
|
20
|
38
|
94
|
66
|
175
|
88
|
93
|
37
|
24
|
|---|
Grant
|
Lancaster 2 |
0
|
0
|
36
|
218
|
134 |
42
|
21
|
25
|
28
|
35
|
15
|
37
|
32
|
69
|
0
|
40
|
8
|
17
|
|---|
Green
|
Juda |
0 |
0
|
100
|
474
|
470
|
194
|
36
|
49
|
2
|
5
|
21
|
29
|
11
|
11
|
1
|
4
|
1
|
0
|
|---|
Green
|
Monroe
|
|
|
6
|
35
|
52
|
3
|
1
|
0
|
0
|
3
|
0
| |
6*
|
4
|
2
|
3
|
1
|
1 |
|---|
Jefferson
|
Lake Mills
|
0
|
0
|
|
45*
|
772
|
15
|
7
|
|
19*
|
5
|
7
|
14
|
21
| |
|
850*
|
9
|
20 |
|---|
Jefferson
|
Watertown
| | | |
39
|
6
|
4
|
6
| |
|
0*
|
8
|
| |
|
| | | |
|---|
Manitowoc
|
St Nazianz
| |
|
0
|
0
|
0
|
2
|
0
|
1
|
0
|
2
|
|
4*
|
10
|
5
|
1
|
0
|
7
|
7 |
|---|
Oconto
|
Mountain
|
0
|
0
|
0
|
0
|
1
|
0
|
0
|
1
|
0
|
3
|
1
|
3
|
4
|
33
|
2
|
0
|
0
|
0 |
|---|
Outagamie
|
Grand Chute
| | | | |
|
14
|
12
|
9
|
0
|
0
|
1
| |
3*
|
1
|
2
|
0
|
3
|
0 |
|---|
Outagamie
|
Seymour
| | | | | |
19
|
9
|
| |
| | | | | | | | |
|---|
Ozaukee
|
Fredonia
| |
0
|
1
|
14
|
12
|
6
|
7
|
32
|
2
|
4
|
0
|
6
|
0
|
5
|
2
|
3
|
4
|
0
|
|---|
Pepin
|
Durand
|
0
|
0
|
1
|
0
|
5
|
6
|
9
|
2
|
1
|
0
|
13
|
|
19*
|
|
17*
|
0
|
2
|
0
|
|---|
Portage
|
Stevens Pt |
|
|
0
|
6 |
0
|
0 |
|
0* |
0 |
0 |
|
4 |
3 |
|
2 |
|
1 |
0
|
|---|
Rock
|
Albany
|
0
|
0
|
|
35
|
157
| |
55*
|
| | |
|
| | | | | | |
|---|
Rock
|
Beloit W
|
0
|
0
|
0
|
12
|
1
|
0
|
0
|
0
| |
| |
| | | |
0
| | |
|---|
Rock
|
Clinton 2
| |
0
|
1
|
35
|
18
|
1
|
1
| |
15*
|
0
|
|
1*
| | |
|
|
0
| |
|---|
Rock
|
Clinton 4
| |
0
|
0
|
2
|
20
|
0
|
0
| |
4*
|
0
| |
0*
| | | | |
0
| |
|---|
Rock
|
Clinton N
| |
0
|
2
|
102
|
27
|
3
|
2
|
5
|
7
|
0
|
0
|
2
|
2
|
0
|
0
|
0
|
1
|
0 |
|---|
Rock
|
Edgerton 1
|
1
|
0
|
1
|
18
|
21
|
4
|
4
|
1
|
1
|
0
|
0
| | | | | | | |
|---|
Rock
|
Edgerton 2
|
0
|
0
|
1
|
18
|
25
|
0
|
2
|
1
|
3
|
0
|
0
| | | |
| | | |
|---|
Rock
|
Janesville N
|
0
|
0
|
0
|
5
|
5
|
6
|
2
|
0
|
1
|
0
|
0
|
|
|
4*
|
0
|
0
|
0
|
0 |
|---|
Rock
|
Janesville S
|
2
|
0
|
1
|
4
|
11
|
0
|
0
|
0
|
0
|
0
|
0
| | |
5*
|
0
|
1
|
0
|
0 |
|---|
Sauk
|
Reedsburg
| |
0
|
1
|
30
|
59
|
8
|
2
|
0
|
0
|
1
|
7
|
13
|
17
|
27
|
10
|
7
|
3
|
1 |
|---|
Sauk
|
Spring Green
|
0
|
0
|
0
|
2
|
6
|
4 |
3
|
2
|
0
|
0
|
0
|
1
|
3
|
2
|
0
|
0
|
0
|
0 |
|---|
Sheboygan
|
Boltonville
| | |
0
|
9
|
|
|
|
| |
0*
| | | | |
36*
|
| | |
|---|
Sheboygan
|
Oostburg
| |
|
0
|
4
|
2
|
8
|
1
|
10
|
1
|
7
|
17
|
3
|
10
|
54
|
13
|
4
|
20
|
5 |
|---|
Sheboygan
|
Sheboygan
|
0
|
0
|
0
|
8
|
6
|
18
|
14
|
11
|
1
|
0
|
0
|
0
|
6
|
28
|
57
|
151
|
177
|
62 |
|---|
Tremp.
|
Ettrick
|
|
5
|
4 |
8
|
1 |
3
|
4
|
5
|
1
|
|
5*
|
11
|
11
| |
18*
|
|
4*
|
0 |
|---|
Walworth
|
Delavan
|
|
0
|
44
|
139
|
53
|
83
|
1
|
2
|
5
|
1
|
0
|
0
|
11
|
14
|
0
|
1
|
0
|
13 |
|---|
Walworth
|
Delavan 2
|
| | |
79
|
143
|
|
11*
|
0
|
0*
|
0
| |
3*
|
13
|
5
|
0
| | | |
|---|
Walworth
|
East Troy
| | |
1
|
34
|
14
|
6
|
0
|
4
|
1
|
4
|
8
|
|
|
| | | | |
|---|
Walworth
|
Sharon | |
0
|
11
|
74
|
116
|
53
|
11
|
17
|
14 |
2
|
6
|
4
|
6
|
28
|
1
|
4
|
|
2* |
|---|
Waushara
|
Almond
| |
|
0
|
4
|
5 |
5
|
2
|
0
|
0
|
0
|
|
27* |
7
|
56
|
152
| |
42
| 2
|
|---|
Waushara
|
W Bloomfield
| | | | | |
8
|
0
|
2
|
0
|
3
|
0
|
2
| |
5*
|
0
|
3
|
4
|
0 |
|---|
Winnebago
|
Omro
|
|
|
|
|
5
|
1
|
0
| |
0*
|
1
| |
15*
|
17
|
31
|
19
|
2
|
1
|
|
|---|
Week 01 (Mar 28-Apr 3); Week 02 (Apr 4-10); Week 03 (Apr 11-17); Week 04 (Apr 18-24); Week 05 (Apr 25-May 1);
Week 06 (May 2-8); Week 07 (May 9-15); Week 08 (May 16-22); Week 09 (May 23-29); Week 10 (May 30-Jun 5);
Week 11 (Jun 6 -12); Week 12 (Jun 13-19); Week 13 (Jun 20-26); Week 14 (Jun 27-Jul 3); Week 15 (Jul 4-10);
Week 16 (Jul 11-17); Week 17 (Jul 18-24); Week 18 (Jul 25-31). * Trap count represents a two-week period or more.