Hi all,
We’re back…
While it seems strange to kick off the scouting and monitoring season with snowflakes falling throughout the region, it also seems completely normal (for Vermont).
Farm and Garden Partners
Before jumping into the notes from the field, we want to first acknowledge this season’s partner farms, as they will be providing valuable regional specific data to help capture the variation in pest and disease activity throughout the state. In the southern region of the state (Arlington, VT) the lovely garden crew at Yellow Barn Farm will be providing weekly scouting and monitoring data. The collaboration with the Garden at Yellow Barn Farm, is a direct outcome of our team’s partnership with UVM’s Extension Master Gardener Program. In the north country, the folks at Boneyard Farm, Hannah and John Doyle, will be sharing their weekly counts and observations from Cambridge, VT. We are so grateful for these two partners as they come on board to support this important work. If you are in their respective areas and rub elbows with them, give them some love.
Week in review
Ok, now on to the pests…Given the recent cooler temps and dry conditions, our pest season has been somewhat unique in comparison to recent years.
We are particularly interested in keeping an eye out for signs of the allium leaf miner, (ALM), as we would like to monitor the expansion of this new invasive pest. Reports from the Finger Lakes region in NY, are showing increased incidence. Growers in western MA and the lower Hudson Valley have also indicated positive IDs. Especially be on the lookout if you are in Southern VT. As a refresher, the adult ALM female fly deposits eggs directly in the leaves of allium plants leaving a distinct line of white dots (egg laying scars). ALM’s impact is seen during the early spring and can be a significant issue for growers harvesting scallions or overwintered onions. The ALM displays a summer hibernation which typically begins around the first week of June and ends around September. So, it typically is not an issue for garlic and onion growers. However, the fall generation emerges just in time to affect any late season alliums (e.g. leeks, scallions).
Maggot pests (e.g. cabbage maggot, seed corn maggot, etc.) seem to be especially thriving this spring. The combination of early season warmth followed by cooler temperatures is a perfect storm for maggot outbreaks. The early season warmth can lead to early emergence, while the subsequent cooler temps can extend egg-laying and egg survival within the cooler soil profile.This seems to be consistent with what we are seeing and hearing about.
A few other highlights from the past week:
Cabbage root maggot: According to the degree day models from NEWA, overwintering populations of cabbage maggot flies are roughly ~80% emerged from their overwintering habitat. Adult females are actively laying eggs at the base of brassica crops. As the cool temps persist, it is likely that the pressure will continue in a serious way.
Flea beetles: Flea beetles are thriving here in Burlington and the southern part of the state and it sounds like they are some large outbreaks in brassica plantings throughout the northeast. Row covers for small seedlings can be an effective strategy for dampening their impact on the sensitive plants.
Cutworms: Cutworms are being seen at our monitoring sites and being reported by many growers. Many growers are seeing them in tunnels and are experiencing significant pressure. Remember that the first generation of cutworm may initially begin to feed on available weeds, so keeping weeds at bay especially around tunnels can help to reduce their impact.
Our website for the scouting reports can be found here. In addition to the pests reported here, our website also has a more comprehensive list of pests. The list also documents the progression of many common pests as they emerge throughout the season.
For detailed management information about these pests, as well as a comprehensive guide to current production and pest management techniques for commercial vegetable crops, check out the New England Vegetable Management Guide. And, as always feel free to reach out to us if you have any questions.
vizzo@uvm.edu & slewins@uvm.edu
| Pest | Crop | Observations |
| Cabbage root maggot: | Brassicas | We are seeing damage in various early season brassicas including radishes. |
| Leek Moth | Onions/Garlic | Adult moths from the emerging overwintering population are no longer showing up in baited traps. Eggs are likely developing on alliums, however, we are yet to see any larvae or feeding damage in any alliums. |
| Flea Beetle | Arugula, kale, broccoli | Beetles are being found in high numbers in many brassica crops. Row covers can be an effective strategy for protecting vulnerable brassica seedlings. |
| Spinach leaf miner | Spinach | Primarily being seen in tunnels, though that seems to be widespread |