Photos by Brian Schultz, Hampshire College, Amherst, MA

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Dale Hopkins
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UConn Extension Vegetable IPM Pest Message & Reports from the Farm, Friday July 8th, 2016 [Comments or answers in brackets/color are provided by Jude Boucher, UConn Extension].

A single European corn borer (ECB) moth was captured at a couple of sites around the state this week and at least one farm still had to clean up first generation larvae in whorl and pre-tassel stage

1 UConn Extension Vegetable IPM Pest Message & Reports from the Farm, Friday July 8th, 2016 [Comments or answers in brackets/color are provided by Jude Boucher, UConn Extension]. Jude Boucher UConn Extension Corn earworm (CEW) moths ranged from 0 to 4/night and thresholds dictated anywhere from no spraying to a 4-day schedule on fresh silking corn. A single European corn borer (ECB) moth was captured at a couple of sites around the state this week and at least one farm still had to clean up first generation larvae in whorl and pre-tassel stage corn. But the first generation is essentially over and we are monitoring for second generation moths in traps. Lots of squash vine borer moths in traps this week 35 at the research farm in Storrs and 33 in Bethany. NH had a site with 133 moths. See last week s message for more info on this pest. No pepper maggot stings were detected at the farms I visited this week and no flies were captured in Berlin, but stings were found, and one fly was captured, by a colleague at Hampshire College in Amherst, Ma. Pepper maggots do not occur on all farms, so preventative sprays are discouraged. Treat for pepper maggots one week after you find stings on cherry pepper fruit or flies on yellow AM traps baited with ammonium hydroxide, hung 20 up in maple or cherry trees along the border of the planting. Dimethoate and Orthene provide 10 days of control and only require 1-3 applications, depending upon how large the population has been allowed to become on your farm over the years. Spinosad (GF 120 Fruit Fly Bait, or Seduce) can work for organic growers, but works best if combined with perimeter trap cropping, where the field is surrounded by a row of cherry peppers, which are treated after the pest begins to lay eggs. Eggs are usually not deposited in peppers until the second week that the flies are stinging the fruit. Note that you are trying to kill the adult flies with this pest and not the hatching larvae, which hatch inside the fruit. Untreated fields tend to have a lot of pods rotting in late August and early September when maggots emerge from the fruit that is a hint you either have untreated ECB or PM infestations. Pepper maggot larvae infest the seed heads so usually go undetected by customers (and often by growers). Pepper maggot fly on trap(yellow stripes/banded wings) Photos by Brian Schultz, Hampshire College, Amherst, MA PM sting(dimple in fruit with white scar) Andy Radin, my counterpart at URI, reported both powdery (PM) and downy mildew (DM) on one farm that is frequently fogged-in near the coast, down in Newport County, RI. I scouted many older plantings of summer squash and other cucurbits across the state this week and did

2 not find any mildews. I m sure PM must be present on an older summer squash planting by now, but nobody has reported it in CT. Pumpkins and other full-season cucurbits usually don t get PM until the plants set fruit which stresses the plants. PM usually starts on the underside of the lowest oldest leaves. Scout 50 lower leaves per week for a dime-sized PM spot. Systemic fungicides work best to reach this infection and slow the spread of this disease, but they are very prone to resistance and each group (chemical family) should only be used a single time each year together with a protectant for fruit rots. A Cadillac program for PM and fruit rots might go something like this and be applied at 10-day intervals once the disease is detected on a farm: Vivando+Bravo, Torino+ Bravo, Quintec+Cabrio (or Dithane), Proline+ Bravo, Sulfur (i.e. Microthiol)+ Bravo. Note that Quintec is not registered on summer green and yellow squash. Organic growers can alternate with sulfur and a potassium bicarbonate product (e.g. Kaligreen or Milstop). We are not quite sure where the downy milder in RI came from, and it has not yet been confirmed in a lab, but it likes cool wet conditions so no doubt that the fogs near the coast could be a contributing factor if this is an outbreak but where did it come from? Remember that this disease has to migrate in from other infected cucurbit crops in the south or west or on transplants or overwinter on cucurbits in the greenhouse. It has not been found in any of the other surrounding states and has only just been found this week in Ontario where it usually comes out of the hundreds of greenhouse cucumber plantings. We are not recommending that cucurbits be sprayed for DM at this time in CT. Wait until you detect it on your farm or at least until we detect it in CT to preserve the effectiveness of the fungicides. Many of our DM fungicides, such as Presidio, are having problems with resistance in recent years. Once DM applications begin, alternate between two effective products. Remember that what was effective last year may not work on the strain that enters the state this year, but might work again next year. When you make your first DM application, be sure to go back in 4-5 days and re-scout the field to make sure that the symptoms on the plants are not still advancing because this disease can defoliate a planting in as little as 7-10 days. Symptoms start as scattered, yellow leaf spots, that turn into brown lesions that are contained by the tiny leaf veins so they tend to be about ¼-1/2-inch squares. Next, the oldest lowest leaves on the vine will begin to cup and then die, and this will spread down the vine with time. Many conventional fungicides can stop this disease in its tracks. Some of the effective products in the past have included: Ranman, Previcur Flex, Forum, Zampro, Revus, Tanos, Curzate and sometimes a phosphorus acid-type product like Fosphite or ProPhyt. Organic growers may slow it down with copper, potassium bicarbonate, Double Nickle, or Regalia if applied starting when it is first detected in CT. See UConn IPM Website for symptom photos ( Steve Bengtson, Cold Spring Brook Farm, Berlin, CT Corn earworm (CEW) - 2 moths caught over 3 nights in two traps (0.33 moths/night) puts us on a 6 day spray schedule. Coragen was used to protect bees which have been very active in our silking corn. European corn borer (ECB) NY (E) = 1, ECB IA (Z) = 0, Total = 1. This is down from 3 last week. Fall armyworm (FAW) trap set up and 0 moths were caught after 5 nights. Pepper maggot trap set up and 0 flies caught after 2 nights. Aphids which were on peppers the last few weeks have disappeared. No spray was needed as natural predators took care of them.

3 Chlorothalonil was applied on tomatoes this week for early blight, which was first found last weekend. Fred Monahan, Stone Gardens Farm, Shelton, CT CEW= 0 moths, but did catch one gypsy moth [Just one gypsy moth you lucky dog! Some of the traps I emptied with growers this week had hundreds! And, because I put the old lures in my back pocket when changing to new lures, they were all over me like wallpaper! Thank goodness they will only be flying for a couple more weeks. Make sure you don t confuse them with CEW moths. GM have large feather-like antennae and larger, brown and black wings. CEW are a light tan with one black dot in the center of the front wings.] Corn earworm moth on corn silk ECB = 1 moth. All of my corn in whorl and pretassel stage were above 15% [infested plants]. I used Coragen on some and Radiant on some. I have been using a product called Birdshield on the sweet corn for a few years now and bird damage has almost disappeared. My greenhouse cukes have been doing well. We did put Hubbard squash in pots at the ends of the greenhouses and treated with grizzly when we saw cucumber beetles. They were planted late and there were already cucumber beetles in the greenhouse cukes. BUT the late planted trap crop did it s job. I see almost no beetles anymore and the cukes show no sign of any beetle damage. All fall brassicas are in trays and we are prepping land for these.

4 The one inch of rain on Monday was what one old timer here used to call a million dollar rain, we got another nice thunderstorm Thursday afternoon. What a relief, because we were spending a lot of time moving water around. On another note that has nothing to do with growing, but with selling our products. We are really enjoying the new Point of Origin law that went into effect last fall. We definitely notice a lot less funny business at local farmers markets. Ian Gibson, Well Stone Farm, Durham, CT The worst pest so far this season has been a lack of rain...having a dry field. Hauling water impedes my ability to properly scout and manage like I would prefer, but it is what it is. Now with the heat and humidity, I'm hoping that we will get enough rain to allow me to get on a regular fungal spray schedule This past week we saw the mass arrival of both cuke beetles and squash bugs on my first planting of cukes and squash - about 5 days after row covers were removed and 3 after rain washed off most of the Surround they were wearing. The bugs have stayed put for the most part and last night I applied a Pyganic/Surround mix at dusk. Monday I also sprayed the lower stem of all my squash (winter and summer) with Entrust and the sticker Nu Film for SVB. Will reapply this coming Monday. My second and third sets of cukes are still under cover for the time being. [The Resource Guide for Organic Insect and Disease Management states that mixtures of pyrethrum and neem [i.e. Azera] has shown good control in some trials for squash bugs. Other growers use it on potato leaf hoppers (PLH) to control both the adults (pyrethrum) and hatching nymphs (azadirachtin or neem) for a longer time than just pyrethrum alone.] For the first time we are battling aphids on peppers and eggplant, despite ladybug populations are higher than anything I have ever seen. I used a new bioinsecticide product, Grandevo, mixed with the sticker Nu Film last week on the eggplant and in two days saw a 95% reduction in population. Peppers are next. Potatoes are starting to show a bit of hopper burn but are setting. I initially intended on covering them, but the time just wasn't there. The Grandevo product is also rated for PLH and has a 5- day efficacy window, so I am going to try it there with a sticker. Not much in the way of onion thrips except a bit on my shallots. If they increase in numbers I will apply one of the several products I have that is listed for thrips - most likely Entrust or Grandevo. Additionally, I will advise this in regards to onions and organic control of onion maggot - use Seduce as opposed to covering unless you have a negligible weed bank. I covered 400 bed ft of onions and opened it to a jungle of pigweed. The 200 bed feet I used Seduce on are in substantially better shape, having avoided a rough weeding. After largely no evidence of them or damage, the cabbage worms have shown, including crossstriped on my Winterbor kale. I am applying XenTari and Nu Film tonight. Flea beetles haven't been much of an issue on tender brassicas as I use Protek net.

I have already been applying Regalia to early tomato plantings, onions, potatoes and eggplant in anticipation of disease season and I will continue that now that the humidity and heat have fully

5 I have already been applying Regalia to early tomato plantings, onions, potatoes and eggplant in anticipation of disease season and I will continue that now that the humidity and heat have fully arrived. Rob Durgy, CT Ag Experiment Station Griswald, CT I saw an adult tomato/tobacco hornworm in the All-American Selection garden last Saturday. [Watch for frass (caterpillar manure) on the black plastic under the vines when you scout next week.] Tobacco hornworm moth (spots on abdomen have faded usually bright orange) Collin Burson, Pinecroft Farms, Somers, CT [reported by J.B.] Sweet corn Their E. Windsor field is all silking and they captured an average of 0.4 CEW moths/night in the pheromone trap which drops them down to a 6-day schedule at this location. In their Somers field, which is also silking, they captured an average of 4.0 CEW moths per night and are on a 4-day schedule. We found the start of Septoria leaf spot (SLS) in the tomatoes and he will use either Cabrio or Bravo for his first fungicide application and then alternate every 10 days or so. Cucumbers and squash We didn t find any cucumber beetles or mildews and no spraying was needed at this time. Peppers we checked young fruit for pepper maggot stings and did not find any. The ECB traps were empty except for hundreds of gypsy moths, which have emerged after denuding

6 many oak trees as caterpillars back during June. No action needed. Some blossom end rot (BER), which is a calcium movement problem. He will try to water more frequently (daily), but with less water each time. Randy Rogowski, Laurel Glen Farm, Shelton, CT [reported by JB] There were no ECB moths in his pheromone traps and we set up a FAW trap in his young whorl stage corn. Potatoes scouting revealed the first few early blight (EB) lesions with the concentric rings and there were plenty of PLH (4/ft of row) on his flowering beans. The flowering beans do not need to be treated, but the potatoes will be protected from EB with mancozeb and PLH with Asana. Remember our experiment on Randy s eggplant from last week. The entire bottom of the lower leaves were covered with aphids after leaving row covers on too long and excluding most natural enemies. But the ladybird beetles (ladybugs) had appeared in greater numbers than I had ever seen a week later. He applied Fulfill to 75% of the planting and left the other quarter unsprayed to see what happens. Good news! All the aphids were controlled by both the lady bugs alone and/or by the Fulfill and lady bugs. Also, the Fulfill, which is supposed to be a selective aphicide, did indeed spare the ladybugs, as well as the parasitic wasps because the leaves also had many aphid mummies this week. It is always better to work with the natural enemies against pests that multiply as fast as aphids do, rather than using broad-spectrum products that can cause secondary outbreaks by eliminating all the beneficials. Ladybird beetle pupae that survived the Fulfill application (lots of them!) Bad news! The aphids moved onto the adjacent husk tomatoes! But so did the lady beetles. They will probably get a shot of Fulfill this week.

Lars Demander, Clover Nook Farm, Bethany, CT [reported by JB] Onions We have been monitoring the progress of onion thrips on Lars crop on silver mulch since the beginning of June.

7 Lars Demander, Clover Nook Farm, Bethany, CT [reported by JB] Onions We have been monitoring the progress of onion thrips on Lars crop on silver mulch since the beginning of June. Up until this week we did not find a single thrips. This week we found a single thrips - just1 on 10 plants. The bulbs are huge and about ready for harvest. The other great thing about using the silver mulch is that it is cooler and doesn t burn the bulbs as they size like black plastic can, which then allows rot organisms into the outer skin. PLH Lars had treated with Asana earlier in the previous week for PLH on his potatoes and beans. There were no PLH present on either crop, but the edamame right beside the beans that were not treated were loaded with leafhoppers. Sweet corn Lars didn t capture any CEW moths in his pheromone trap for the 4 nights before we checked on Tuesday = no spray needed. Between 6/28 and 7/1 he captured an average of 0.7 which dictates a 5-day schedule on silking corn. We set up a FAW trap in young whorl stage corn. Brassica We scouted and 30% of his plants were infested with imported cabbageworm (ICW). Since you can kill ICW with anything, he will use up some of the Dipel he has on hand. Peppers we are seeing some BER. ph and Ca levels are in the right place. Water daily to help move more Ca out to far end of the fruit where it helps to build cell walls in the rapidly expanding tissue. Lars is raising a few giant pumpkins so is monitoring for squash vine borers. He found a total of 33 borer moths in his trap last week and has treated the bottom foot of his plants for hatching larvae. Lars Demander, Clover Nook Farm, emptying SVB moths

8 Steve & Ben Berez, The Farm, Woodbury, CT [reported by JB] Sweet corn green tassel corn had 2% ECB infested plants, pre-tassel plants had 4%, and late whorl stage plants were free of larvae. Tomatoes we found the star of a little leaf mold. They were a little late with their second early blight fungicide application. Eggplant and peppers looked great. No sign of pepper maggot stings and no ECB moths flying. Pumpkins and winter squash They had poor emergence in one late field due to the dry weather and another field required cultivation because the herbicide didn t activate as well as it should have. We didn t find any mildews on any of their cucurbit plantings and very few beetles or squash bugs. Cole Van Seters, Freund s farm Market, E. Canaan, CT [reported by JB] Squash and asparagus required some weed control, but did not require and other treatment. No ECB moths were captured. Josh Bristol, Bristol s Farm Market, Canton, CT [reported by JB] Sweet corn 0.01 CEW moths/night = no spray on silking corn. 0 ECB moths in traps. Pretassel stage corn had just 2% of the plants infested and late whorls stage plants were clean. Onions Josh also has his onions on silver reflective mulch and they are just about ready for harvest too. We found an average of 1-2 thrips per leaf. The threshold is 3/leaf. He will probably harvest before treatment is required. This shows that onions can still become infested on silver mulch, but who knows how bad the infestation might have been without it. When my colleagues in MA had two growers try plantings on both silver and black mulch, they found that the silver always had fewer thrips, but that it seemed to reduce the size of the bulbs and yield. I don t see any sign of small bulbs on either of the farms using the silver mulch this year in CT. Summer squash no powdery mildew Peppers no pepper maggot stings. Owen Jarmoc, CT Valley Growers, Enfield, CT [reported by JB] We scouted 7 cucurbit fields and only found cucumber beetles (1-2/plant) on one back field. There were also a few scattered squash bugs on plants near the edge of that field. He will treat just that field with Sevin. Almost all his varieties are powdery mildew resistant and we did not find any mildews in any of the fields that were scouted. Peppers no pepper maggot stings were found on fruit. That s all for this week. The next IPM pest message will be sent on Friday afternoon July 15th.

Rob Maddox, Sun One Organic Farm, Bethlehem, CT

Rob Maddox, Sun One Organic Farm, Bethlehem, CT UConn Extension Vegetable IPM Pest Message & Reports from the Farm, Friday June 24th, 2016 [Comments or answers in brackets/color are provided by Jude Boucher, UConn Extension] Jamie Jones, Jones Family