Weekly Slug Trapping Data for Wisconsin Farmers
Week of May 18-24
Slugs were captured in over half of the counties that reported this week, but numbers remain low with an average of less than 1 slug per shingle trap in all counties except for Clark.
Some sites were still being planted and shingle traps were removed for field operations. Slugs were observed around, but not under, the shingle traps at several sites (these are not reported in the weekly counts). Slug eggs were also reported under shingles in 3 counties.
As corn and soybeans start to emerge, make sure you are scouting your fields and looking for evidence of slug feeding (damage to newly emerging plants and slime trails are things to look for). Slugs are nocturnal, and depending on when you scout, slugs may not be present in the field.
Three new monitoring sites in Shawano, Oconto, and Outagamie are online and will be contributing monitoring reports.
| County Name | Average Slug Count Per Trap | Total Traps Per County | Total Slugs |
|---|---|---|---|
| Chippewa | 0.83 | 30 | 25 |
| Clark | 1.2 | 5 | 6 |
| Crawford | 0.00 | 5 | 0 |
| Dane | 0.33 | 39 | 13 |
| Fond du Lac | 0.00 | 75 | 0 |
| Grant | 0.24 | 50 | 12 |
| Iowa | 0.13 | 15 | 2 |
| Kewaunee | NR | 20 | NR |
| Oconto | NR | 20 | NR |
| Outagamie | NR | 20 | NR |
| Ozaukee | NR | 20 | NR |
| Sauk | 0.00 | 5 | 0 |
| Sheboygan | 0.05 | 20 | 1 |
| Winnebago | 0.1 | 20 | 2 |
NR indicates “no recording” from that county.
Welcome to the second year of the SlugNet project in Wisconsin, a new initiative aimed at monitoring slug populations across the state. This effort uses a citizen science approach, relying on the valuable contributions of participants across our state to collect slug population datain field crops, with a focus on conservation cropping systems (e.g., reduced tillage, cover crops).
UW-Madison Extension and external partners are tracking slug activity to identify patterns in their emergence and damage. The project’s goal is to understand the key factors that lead to severe slug outbreaks so we can help farmers take preventive steps—especially since current chemical control methods are limited. As planting gets underway, be prepared for slugs since we are working in wet and cool weather conditions.
The team will be regularly sharing updates on slug counts from participating counties and observations of feeding damage in this weekly article. In the first year of the project, the team is excited to gather as much data as possible.
For those interested in helping us understand slug activity in Wisconsin crop fields, there’s still time to get involved! Visit the SlugNet project website for more information about the project’s goals, protocols, and how to participate in slug monitoring. Thanks to all volunteers who are already monitoring traps for slugs!
Slug Management Resources
Visit our partner, the Bick Lab, for more field crop insect pest information
See our Managing Slugs in Wisconsin Field Crops article for more information on slug pests in Wisconsin.