By Shelby Fleischer
Corn earworm (CEW) catch is strong in southern Delaware, suggesting successful overwintering in the DelMarVA. Positive values also occurred in southeastern PA (Bucks and Lancaster counties) and along the Hudson River. Overall, catch in PA is low to absent. Tasseling and silking corn will be very attractive. Moths will also lay eggs on many host plants when corn is not available. Tomatoes and hemp make a good host (CEW is also known as “tomato fruitworm”).
European corn borer (ECB) counts are low. Scout for feeding damage and shothole patterns.
Fall armyworm (FAW) counts are low. Captures this time of year may be the non-target capture of wheathead armyworm, which is not a pest.
Average weekly catch: moving average for the last 7 days. The average catch per night (catch/number of nights trapping), divided by the number of nights where data exist, multiplied by 7. Weeks where all the average-catch-per-night values are nulls are treated as if no data exist for that week. Empty cells indicate no trap for that site.
| County | Town/Farm | CEW | CEW | CEW | ECB | ECB | ECB | FAW | FAW | FAW |
|---|
| | | 27-May | 3-Jun | 10-Jun | 27-May | 3-Jun | 10-Jun | 27-May | 3-Jun | 10-Jun |
| Bucks | Bedminster | null | null | 3 | null | null | 0 | | | |
| Centre | Rock Springs | null | null | 0 | null | null | 0 | null | null | 0 |
| Lancaster | Landisville | null | null | 0.6 | null | null | 1.2 | null | null | 0 |
| Lancaster | Neffsville | null | null | 0 | null | null | 0 | null | null | 0 |
| York | York | null | null | 0 | null | null | 0 | null | null | 0 |
ThresholdsReproductive (tassel/silk) and late vegetative corn attracts moths. Shorten spray schedules when populations increase. If CEW is not a problem, then consider ECB.
| Thresholds Based on CEW | Catch Per Week | Spray Frequency (Days) |
|---|
| Almost absent | 1–13 | 7+ |
| Very low | 14–35 | 5–6 |
| Low | 36–70 | 4–5 |
| Moderate | 71–349 | 3–4 |
| High | > 350 | 2–3 |
| Thresholds Based on ECB | Catch Per Week | Spray Frequency (Days) |
|---|
| Almost absent | < 14 | 7+ |
| Very low | 15–35 | 6 |
| Low | 36–70 | 5 |
| Moderate | > 70 | 4 |
Source : psu.edu