Eggplant have minor amounts of flea beetles and leafhoppers present. I will keep an eye on the populations.

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1 UConn Extension Vegetable IPM Pest Message & Reports from the Farm, Friday June 19, 2015 [Comments or answers in brackets are provided by Jude Boucher, UConn Extension] Steve Bengtson, Cold Spring Brook Farm, Berlin, CT ECB I (Z) 5, ECB II (E) 0, Total 5 moths, down from 6 last week. 2 fields scouted in whorl stage resulted in 0% to 6% infestation. CEW traps were setup on 6/14 and had 0 moths as of 6/17. No sign of early blight yet in our early tomato fields. Peppers received their second soil fungicide application to ward off phytopthora. This week Revus was applied right after we received 1.7 inches of rain. Summer squash has powdery mildew and received a spray of Pristine before the rain. Doesn't seem to have been very effective. The golden zucchini variety "Butta" seems to be especially susceptible to powdery mildew. Flea beetle and a few cucumber beetle were found in our muskmelon field. I will spray with spintor to control the flea beetle and will keep an eye on the cucumber beetles. Eggplant have minor amounts of flea beetles and leafhoppers present. I will keep an eye on the populations. Jamie Jones, Jones Family Farms, Shelton, CT Been mostly busy with strawberries. Noticed leaf hoppers on potatoes today. Pumpkins up with first true leaves, no issues with them, yet... Bob Handel, Handel Farm, East Hartford, CT Scouting pretassel sweet corn - 2% ECB. Did find a lot of lady bugs. No early blight in field tomatoes, but still getting blossom end rot in my greenhouse tomatoes. Bruce Gresczyk, Jr., Gresczyk Farms, New Hartford, CT Corn: I am yet to find any significant amounts of ECB or any Armyworm, but we are a poor gauge as we are fairly isolated and in the past 5 years we have only crossed the threshold in one or two fields.

2 Tomatoes: Last week I found some Early Blight on one block of tomatoes it was only on leaves that were touching the raised beds plastic. We removed the bottom leaves (We were going to do it anyways for air movement) and sprayed them with copper and bravo. Other than that the tomatoes are remarkably healthy and growing great. Cucurbits: I found Powdery Mildew as well as a single cucumber beetle in our early summer cucurbits. We will be treating with Pristine for the PM any recommendations for the Cucumber Beetle. [Sevin or a synthetic pyrethroid if you find 0.5 beetles/plant for cucumbers and melons and 2 beetles/plant for squash and pumpkins. Organic growers have Entrust, PyGanic, and Surround but they do not do a stellar job on cucumber beetles. Row covers until bloom, perimeter trap cropping and distant crop rotation work better]. Potatoes: I am yet to find Colorado potato beetle or leafhoppers on our Potatoes, but I expect to see them soon! Fred Monahan, Stone Gardens Farm, Shelton, CT Brassicas have diamondback moth, I am planning to spray with Coragen. The tomatoes that were under Remay are showing early blight and Septoria. Basil had definite signs of downy mildew but alternating Ranman and Quadris has stopped it in its tracks and the basil is very nice. Beans and potatoes both had leaf hopper. Dimethoate took care of both. Potatoes have Colorado potato beetle. I have been alternating Coragen, Nuprid and Radiant on three year rotation. This year I should use Radiant. Any other suggestions to throw in the mix? [Agri-Mek, Avaunt and a neonicitinoid like Admire are all registered on potatoes and work well. You should only use one family on one of the two CPB generations each year, not all year long but when you wipe out the first generation you often don t have a second.] ECB moths in traps = 4 moths Pretassel 4% ECB [infested plants] Late whorl= 0 % [infested plants] Mid whorl= 0% [infested plants] Silking corn=0% but had Remay on until last week CEW moths in traps = 0 We planted 2.5 acres of asparagus 3 weeks ago. We hit the rainfalls just right and have not had to irrigate. It is time to hoe in the trenches to level as the asparagus is all waste high or taller and all ferned-out. I hope all this hand work is worth it in coming years. We are in the middle of sanitizing tomato stakes, we soak them in bleach solution for 1 hour each batch. We use an old bucket from one of the front loader tractors as the tub. It takes some time to sanitize them all but since we started heat treating seeds, sanitizing trays, and sanitizing

3 stakes we have eliminated any bacterial problems on tomatoes and have almost eliminated all copper sprays in the fall. Cecarelli Farm, Northford, CT [reported by JB] Only a slight increase in ECB infestation this week. The first three plantings in the late whorl to pre-tassel stages of growth had 0 to 4% of the plants infested with larvae. The threshold at pretassel is 15%. We set up pheromone traps so we can report moth numbers next week. No early blight on their tomatoes. Suckers were removed up to the first fruit cluster and the plants were all stakes and trellised. This allows for better air movement through the plant canopy and quicker leaf drying. Remember that tomato fungal diseases develop and advance faster when leaves are wet longer. Oxen Hill Farm, W. Suffield, CT [reported by JB] All 4 potato fields had high levels of potato leaf hoppers this week up to 9 per foot of row. Potatoes are very sensitive to this pest and the threshold is 1 per 50 leaves or 1 per sweep, if using a sweep net, or yield is dramatically affected. Since it is such a large amount of organic potato acreage, he will try to use PyGanic for the PLH and later PyGanic with neem or azadiractin (for hatching nymphs) to extend the short residual period of effectiveness of the pyrethrin. The potato fields adjacent to fields that had CPB last year had them again this year. Remote fields had much lower numbers or none. Organic growers should only use Entrust on one generation of CPB every other year or risk losing that valuable tool to resistance. In the literature, it says that if you use any pesticide on this pest for 6 generation, or three years in a row, that they will learn to eat it. You can alternate with Mycotrol-O, with the fungus Beauveria bassiana in it, after rotating fields when beetles are at relatively low levels to rest the Entrust. I recommended hilling and covering the field with row covers before the pests came in, but he wasn t ready to make that investment in row covers yet. It can be done even on 20 acres we have sweet corn growers that cover 20 to 45 acres with row covers. Josh Vincent, Vincent Farm, W. Suffield, CT [reported by JB] He captured 5 ECB moths in pheromone traps and his first two sweet corn fields had 0-4% of the plants infested. Josh set up his CEW trap this week so should be able to provide trap numbers next week when his first field silks. Tomatoes were free of diseases and ready to be pruned and staked or trellised. Michaele Williams, Vegetable Crops Field Manager, Bishop s Orchard, Guilford, CT [reported by JB]

4 Michaele sent in this picture of her summer squash this week and she was afraid it may be a disease from out west called cucurbit yellow vine disease (CYVD) spread by squash bugs. I found CYVD on pumpkins in Ellington about 12 years back and we got it confirmed in a lab out west. We haven t seen it since. It also affects the whole plant, not just the lower couple of leaves. These lower yellow leaves in the picture are the result of a yellow marker gene for the precocious gene that masks watermelon mosaic virus II in squash. The plants will develop normally and bear fruit which will mask the green discoloration on the fruit usually caused by WMV II. Many different farms around the state are using these precocious gene varieties, and the plant are all fine and growing and producing well. It is nothing to worry about. Byron Graham & Carolyn Canfield, Meeting House Farm, New Milford, CT [reported by JB] We scouted their kale and other Brassica crops and found 60% of the plants infested with diamondback moth larvae this week. I don t think I found another field of Brassica crops in the state that exceeded 20% this week and required a spray. They should either use the B.t. aizawai strain found in XenTari or Agree or use Entrust to stop the infestation. It is important to alternate IRAC resistant groups with this pest because resistance occurs quickly with DBM. Steve and Ben Berezc, The Farm, Woodbury, CT [reported by JB] Their oldest sweet corn field was in the late tassel stage and had 16% of the plants infested. Next week when it reaches the pre-tassel stage it will be over threshold (15%) and require a treatment. Tomatoes were disease free and about to be pruned and staked. Sara Blersch and Dan Slywka, Daffodil Hill Growers, Southbury, CT [reported by JB] We found bacterial canker on one row of tomatoes. Because all the plants were handled while planting it is too late to cull the infected plants to stop the disease. This disease can usually be controlled with hot water seed treatment. Weekly copper applications may or may not slow it

5 down depending upon how aggressive the strain of canker is and the weather conditions throughout the season. Canker can be easily recognized because it is the only disease that causes the edge or margins of the leaves to scorch yellow and then brown. Never prune plants that have canker or the bacteria can enter the pruning wounds and kill the plants within days. I think the antibiotic streptomycin (Agri-Mycin-17) can still be used in the GH preventatively to stop BC, but the use of antibiotics in agriculture is being discouraged these days to help prevent world-wide antibiotic resistance. There are several Bacillus microbial products available for organic growers. Mike & Megan Grogan, Autumn Oak Farm, Tolland, CT They had more than 50% of their ferns infested with asparagus adults and larvae so will treat them with Radiant. I have found that one such treatment can sometimes knock the beetle population down on a site for several years before retreatment is required. We found bacterial leaf spot on their two rows of peppers. This is the most common foliar disease of peppers but it is very unusual to find this disease in a small planting. It arrives in infected seed and the more seeds you plant, the better your chances of having infected plants so it usually only hits large plantings. Again, it can be prevented with hot water treatment see the article on the UConn IPM web site under vegetables and general articles: If you find it in the field before it spreads you can rogue out the infected plants and a few without symptoms on each side and sometimes that will stop the spread. Copper applications at 7-14 day intervals is the usual treatment along with a 3 year crop rotation to make sure the stems of the plants are completely broken down. Mike and Megan will remove the plants and get them off the farm. Jude Boucher, UConn Extension One of the hardest lessons that a new grower has to learn is how to control weeds on their farm. This is particularly challenging for organic growers who can t just reach for another herbicide. This winter Eric and Anne Nordell, from Lancaster County, PA spoke at the CT Vegetable & Fruit Conference and shared their system of using cover crops, summer fallow, shallow tillage and crop rotations to lower the soil seed bank and avoid the necessity of a lot of hand weeding. Even the conventional growers raved about their talk and knowledge of farming and it was the highest rated talk we have ever had at the conference. I have been handing out their manual and DVD to the new growers on the IPM program this year. The DVD is $15 and the manual $5 if you would like to purchase one. I m out of DVD s right now but we just reordered. I always tell new growers that you have to control the weeds before you can start farming and it is always best to have a backup plan, and a backup to your backup, just in case your first plan fails. You ll find that weed pressure varies dramatically by field, season, time of year, weather conditions, soil types, crop competition, etc. You may plan on cultivating, flaming or using a living mulch for weed control but weather conditions and heavy soils can prevent you from getting in at the right time, and you might find a jungle growing up. Ask yourself, what is your backup plan? It may be as simple as mowing the weeds between the plastic mulch or rows. I m trying three different cover crops or living mulches between the plastic this year and cultivating crops in another field. Because I only have a few hours per week at the research farm, I use a BCS sickle bar mower so that I can mow weeds if they get too tall, in any weather condition, since rain can bog down a rotary mower, and I may not make it back for a week. I can always cheat and use a post-

6 emergence or burn-down herbicide between the plastic too. Gardeners just give up and go to the grocery store but you re a pro now so what s your backup plan? That s enough for this week. I ll send you another update next Friday, June 26 th.