0-0.2 no spray days days days >13 3-days

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1 UConn Extension Vegetable IPM Pest Message & Reports from the Farm, Friday, Sept 2nd, 2016 [Comments/answers in brackets/red by Jude Boucher, UConn Extension]. Jude Boucher UConn Extension Pepper maggots are emerging from red peppers now and causing fruit to melt down with soft rot that enters the wounds. I received an from colleagues in NH this week, letting me know that PM s have spread across southern NH for the first time this year. They were also on almost every farm I visited in CT this year (many for the first time), including the UConn Research farm where I would have loved to have had them when I was doing my dissertation years ago. Because the maggot hides inside the seed head, and peppers are often sold while still green with them inside, growers often make the mistake of thinking that this is not a big problem. However, since the females lay 50 eggs each, it can turn into a big problem in a couple of years once they arrive on a farm. Check the seed heads now on some of the rotting peppers in your field and see if they are honeycombed from maggot feeding. If an infestation has started on your farm this year you should plan to control the adult flies next July with dimethoate, Orthene or spinosad (GF-120 Fruit Fly Bait or Seduce). Uncontrolled populations can infest 80% of the fruit and cause many pods to rot at this time of year. What to watch for this week - Cercospora leaf spot on beets, spinach and chard. Aphids and Alternaria leaf spot come on fast in the fall on B. sprouts and other Brassica crops. One grower in New Hartford just reported problems with slugs on Brassica crops. Growers on Long Island are having trouble with loopers and fall armyworms on their tomatoes this week, and tomato fruitworms will start to be seen as all the corn matures and is no longer as attractive a host. ALERT All cucumbers and melons should be protected from downy mildew (DM) at this time. Rainman may not be providing sufficient protection from this strain of DM. It is recommended to try other materials, such as Tanos, Curzate, Previcur Flex, Revus, Zampro, Forum. Organic growers should be protecting their cucumbers and melons with preventative applications of available products such as: copper, DoubleNickel or Regalia. Pumpkins and winter squash We did not find any DM on pumpkins or winter squash again this week. They should be protected from powdery mildew and fruit rots at this time, not DM. You may actually get these crops harvested this year without needing a DM material in your spray mix. Remember that DM only defoliates, it does not rot the fruit, so once fruit are sized, you won t need to control this disease. Corn earworm (CEW) moths in pheromone traps ranged from 0.33 to 12.5 moths per night this week, down slightly at most, but not all locations. All growers are now spraying silking corn on a 6, 5, or 4-day schedule. Moths per night Spray interval no spray days days days >13 3-days

2 Fall armyworms ranged from 0-1 moth in traps. One farm in Shelton and another in Somers have been experiencing heavy pressure in young corn. Scout your pre-tassel stage corn, if you have any left. This week, one grower reported that he has been having good control with Coragen. European corn borer (ECB) trap captures ranged from 0-3 moths this week. Pepper fields do not need spraying for borers at this time. No sign of a third generation yet. UConn Research Farm 1.1 CEW moths per night calls for a 4-day schedule on silking corn. Zero FAW moths, and just 1 ECB moth. Follow-up on the saddleback caterpillars found last week: Saddleback caterpillars on corn, Photo by Wayne d Entremont of Amston, CT Wayne in Amston reported getting stung a second time by this pest, which has convinced him to give up growing sweet corn. Rob Durgy, our former Plant Diagnostician here at UConn, and the current Farm Manager of the CAES Griswold Research Farm, also reported that he was stung by one while picking his sweet corn this past weekend. He said it was much worse than stinging nettle. I hope this doesn t become a common problem! Anybody else seen these or had an unpleasant close encounter with them? Steve Bengtson, Cold Spring Brook Farm, Berlin, CT CEW counts dropped this week to.5 per night putting me on a 5-6 day schedule on fresh silking corn. 1 ECB moth caught this week in my traps. Downy mildew showed up in our cucumber field but just in one area. It seems to be under control for the most part. I sprayed Quadris and Revus last weekend and it seems to be keeping

3 it at bay. I will search my pesticide cabinet for another low day to harvest product to use this weekend. So far no sign of downy mildew in our greenhouse pickles. Bob Handel, Handle Farm, E. Hartford, CT Earworm report - getting 6 moths per night, so on a 4-day schedule. Sorry I have not been reporting, but my computer keeps getting a virus and I m keeping the Geek Squad in business. Fred Monahan, Stone Gardens Farm, Shelton, CT It has been very dry and irrigating crops and moving water has been a priority. This is two years in a row, and makes me think about weather pattern change. It seems like if we want to grow food in the future we need more water. We are planning on pond expansions after the growing season. I did heat treat my basil seed in the spring and it seemed to hold off the downy mildew early on basil, but now even with spraying with Ranman and then Quadris our basil is poor. ECB = 1 and has been holding at 1/ week FAW in Tasseling corn=26% FAW in Pre tassel corn=36% FAW in Late whorl corn =32% Grizzly last year did nothing for FAW. This year I am using Coragen and the corn is clean after spraying. CEW counts in one field are 6/ night CEW counts in one field are 4/night CEW counts in a third field are 2/night Eggplant had spider mites Downy is on cukes, Ranman doesn t seem to work as good as on other years, what should I use this week? [You might try Previcur Flex, Tanos or Revus.] We are still seeding fall radishes, Asian greens, and lettuces to the field Also putting scallions in hanging baskets in two greenhouses, this worked very well last fall and winter. You don t need to keep greenhouses that warm (just above freezing) These scallions and Asian greens provide something green for customers through the winter. They go well with our stored carrots, beets, potatoes, etc.. We are making plans to bring tomatoes to be processed into tomato sauce, salsa, and Bloody Mary mix and the processor we use in New Haven is backed up. This is a good sign, a lot of other growers are taking advantage of different ways to sell there excess tomato crop!!! Jamie Jones, Jones Family Farms, Shelton, CT Hard to believe its August [sent on 8/30] and we are harvesting pumpkins One field the leaves are down, the cucumber beetles are gnawing on the stems, so we decided to pick them up. Figure they should be better stored in the barn now. Quality is pretty good, but you can tell they weigh less than usual.

4 Randy Rogowski, Laurel Glen Farm, Shelton, CT [reported by J.B.] Phytophthora killing pepper plants they go down like dominoes! Peppers Phytophthora has just started to kill plants on the edge of Randy s planting. He will dispose of all the sick plants off farm, pick up the plastic where the disease is killing plants, and break the bed with a shovel (leaving the trickle tape intact) to keep the swimming spores from moving farther down the bed and contaminating more land. It is recommended to remove a few healthy-looking plants beyond where the plants are dying because some may be infected, but just not showing symptoms yet, then break the bed just beyond that. He should also not plant a susceptible host such as Solonaceous, Cucurbit or legume crops there in the near future, since the pest needs three things to spread: the long-term spores must be in the soil, a host must be present, and it needs hours of soil saturation for the swimming spores to emerge and infect plants. Containing the spread of this disease is of utmost importance since it essentially can stay in infested soil forever. He should also try to improve the drainage in that part of the field since the presence of this disease shows that it stayed saturated for a prolonged period. This was close to where the water runs off the barn roof. Beets We found Cercospora leaf spots starting. Copper products seem to work as well as anything against this pest. Winter Squash and pumpkins no downy mildew was found.

5 Cercospora leaf spot on beets Lars and Eric Demander, Clover Nook Farm, Bethany, CT [reported by JB] Sweet corn Lars captured 12.5 CEW moths per night in his trap, which calls for a 4-day schedule on silking corn (just barely) - the same as last week. He only captured 1 FAW moth. Brassica Lars applied Assail and dropped the caterpillar infestation from 50% last week to 0% this week. He tried Asana on the Kale for white flies but had no luck. The Assail probably would have made out better. Pumpkins and winter squash were scouted and no DM was found. Swiss chard Cercospora spots were found. Dan Slywka, Daffodil Hill Growers, Southbury, CT Sweet corn Dan captured 5 CEW moths per night this week, leaving him on a 4-day schedule on silking corn. He didn t capture any FAW moths for the second week in a row and his pretassel stage corn was clean (0%). Pumpkins and winter squash no DM found. He will just treat for PM and fruit rots with sulfur and chlorothalonil (i.e. Bravo). Ben and Steve Berecz, The Farm, Woodbury, CT [reported by JB] Pumpkins and winter squash most of the pumpkins were ready for harvest, but some were being harvested by the deer, despite their attempt to stop them with a repellent. Installing a 3-

6 dimentional electric fence before they get the taste for your pumpkins is the best way to keep these beasts at bay. No DM was found. They will continue to spray for PM and fruit rots until they get most of the fruit out of the field. Pumpkin eaten by deer they love the seeds! Josh Bristol, Bristol s Farm Market, Canton, CT [reported by JB] Sweet corn Josh captured 0.33 CEW moths per night which moved him from a 5-day schedule last week back to a 6-day schedule this week on silking corn. Peppers - Only 3 ECB moths were captured. He did find a few borer larvae in his corn, but not enough to have made it worthwhile to spray. Cucumbers no DM was found. Copper was recommended. Brussel sprouts no caterpillars were found, but one of his two varieties of sprouts had no sprouts on the plants. A whole block of them. I thought that this must have to do with the hot, humid weather that we had in weeks past, just as it caused the eggplant or peppers on some farms to drop flowers. I brought it to the CT Ag Experiment Station on my way home and they agreed that it was caused by the heat. Another variety made sprouts but is not resistant to Alternaria leaf spot, so shall remain nameless, as this disease can steal your crop as the fall morning dews are heavy on the plants.

7 Full-sized Brussel sprouts plants without sprouts! Owen Jarmoc, CT Valley Growers, Enfield, CT [reported by JB] Pumpkins and winter squash No DM was found. He should be harvesting in 2 weeks, just after all the tobacco is in the barns. Until then, he will continue to protect the leaves and the fruit with sulfur and chlorothalonil. Brian Kelliher, Easy Picken Orchard, Enfield, CT [reported by JB] Last week Brian reported that he thought a parasitoid was attacking and helping to control the cross-striped cabbageworm (CSCW) on his farm. He was right! This week I noticed the white cocoons of the parasitoid at other farms and even found a dead CSCW caterpillar beside the cocoons once. This is a parasitic wasp in the family Braconidae, which is closely related to the two parasitoids that kill imported cabbageworms. It is called Cotesia orobenae and is quite common and effective at controlling the CSCW in warmer states like VA. It lays many eggs in a single caterpillar and usually about 9 larvae emerge to spin cocoons beside the dead CSCW. One paper in the literature describes how using broad-spectrum insecticides on a farm can kill these wasps and cause outbreaks of CSCW. Conventional growers should alternate between two selective products that spare beneficials when controlling caterpillars on Brassica crops, such as the insect growth regulator Intrepid and the group 28 product Coragen. Organic growers will spare the wasps if they use a B.t. product such as XenTari or Agree. Spinosad, the active ingredient in Entrust, has been shown to be a little tougher on some parasitoids, but a single application seems to leave many wasps alive and well, from what I have observed.

8 Cotesia orobenae pupal cases: note how the top of two cases are open which means the wasps have emerged to hunt more CSCW caterpillars. Leanne Pundt, Greenhouse IPM Educator, UConn A workshop on: Practical Applications in Greenhouse Nutrient Management will be held at the CAES, Jones Auditorium, 123 Huntington St., New Haven, CT on Sept 27. Contact Leanne Pundt to pre-register ($25) or for more information: , leanne.pundt@uconn.edu. That s all for this week. The next IPM pest message will be sent on Friday afternoon September 9th.