With increasing temperatures, it is plausible that a critical treatment window for controlling White Pine Weevil (WPW) will be present early next week, throughout many areas of NJ. Factors leading to this post include increased air temperatures and climbing growing degree-days (WPW adult movement and egg laying is around 7-58 growing degree-days (GDD50)), and most importantly rising soil temperatures as this pest typically begins movement with soils hovering around 50F. All of these factors lead to the possibility of WPW movement early next week and growers may wish to utilize a preventative, long lasting residual spray (pyrethroids) to target adults before they begin egg laying.
So we have:
- NJ will be within the GDD window for adult movement and approaching egg laying (7-58 GDD50)
- Soil temperatures in some areas may be close to 50F.
- Increased air temperatures and insect mobility
| White Pine Weevil (Pissodes strobi) – potential for emergence as of 3/6/2026 | |||||||||
| Region | Location | CODE | METRIC | FRI | SAT | SUN | MON | TUES | WEDS |
| 6-Mar | 7-Mar | 8-Mar | 9-Mar | 10-Mar | 11-Mar | ||||
| Southern | Upper Deerfield | NJ50 | GDD50 | 0 | 0 | 9 | 13 | 18 | 31 |
| High Temp [ºF] (Average) | 49 (43.5) | 52 (50.5) | 63 (52) | 67 (45) | 71 (62) | 71 (60.5) | |||
| 24hr Average – Soil TEMP [ºF] | 47.1 | <- (This will change over time / no prediction available) | |||||||
| Central | Freehold / Howell | NJ50 | GDD50 | 0 | 0 | 4 | 6 | 9 | 17 |
| High Temp [ºF] (Average) | 42(39) | 49(48) | 62(51.5) | 69(56.5) | 74(63) | 70(59) | |||
| 24hr Average – Soil TEMP [ºF] | 40.7 | <- (This will change over time / no prediction available) | |||||||
| Northern | HACKETTSTOWN | G5633 | GDD50 | 0 | 0 | 3 | 3 | 6 | 17 |
| High Temp [ºF] (Average) | 41(37.5) | 47(45.5) | 61(49.5) | 69(55) | 76(63) | 68(55) | |||
| 24hr Average – Soil TEMP [ºF] | 34.1 | <- (This will change over time / no prediction available) | |||||||
| USPEST.ORG – Model: simple average/growing degree-day, Min: 50F – Max: 95F, NMME forecast | |||||||||
| Forecast: 7-month NMME based seasonal climate forecast (USPEST.ORG) – Subject to change regularly = Check Often | |||||||||
| Air temperatures: Weather Underground (https://www.wunderground.com/) and NEWA: (https://newa.cornell.edu/) | |||||||||
| Soil temperatures (10cm): https://www.greencastonline.com/tools/soil-temperature | |||||||||
| Compiled by Waller. T. 3/6/2026 [twaller@njaes.rutgers.edu] | |||||||||
