VERMONT VEGETABLE AND BERRY NEWS
June 1, 2000
Compiled by Vern Grubinger, University of Vermont Extension
(802) 257-7967 or  vernon.grubinger@uvm.edu

REPORTS FROM THE FIELD (as of May 23)

(E.Hartland)  Despite alternating frost threats and cool weather we are putting out tomatoes and peppers and covering them. About half the sweet corn crop is in. Bearing strawberry beds look pretty weak from the winter and are nowhere near 10% bloom at this time. Onion and leek transplants getting their feet under them but because of the cool damp weather all the lettuce transplants from different seedings are bunching up in the field. There is going to be one gob of lettuce ready about June 25. Weed problems are minimal due to the cold soils. Striped cuke beetle is in the cucumber greenhouse. Another pretty good year of greenhouse bedding plant sales.

(Saxtons River) Full bloom in blueberries should occur this week for most of my varieties. Early varieties are already dropping petals like crazy. Some sun and insect pollination activity would be most appreciated. Crop looks heavy, which figures since last year it was virtually nonexistent. Primary infection of mummy berry looks to be light this year in spite of good conditions for the production of spores. One properly timed application of Funginex seems to take care of this disease. (Since this material works so well, the chemical company has decided not to produce it any more.) Am a little behind on the fertilization, but will complete the first application this coming weekend.  New research has shown that up to 90% of nitrogen is lost to run-off when fertilizer is applied in April before leaves emerge. The new recommendation is to make the first application during bloom and the second one 6 weeks later (in New Jersey.)  I make my second one after 4 weeks to prevent late growth and subsequent winter damage. I have used this schedule for several years now, and it seems to work fine. I now see fewer signs of nutrient deficiencies (magnesium and nitrogen are the most common ones on my soil) during the summer. Winter damage has been no worse than usual.

(Marlboro) Puddles in the vegetable gardens, raspberries and blueberries look healthy so far but with the wet weather just waiting for the diseases to set in, maple trees look great this year.

(Charlotte) Still too wet to put equipment on field. Wetness beginning to affect the greenhouses, soil inside not drying out as usual resulting in poor germination resulting. Seen CPB and plenty of flea beetles. Mowed chest-high rye to try and let fields dry. Muskrats have burrowed holes through dam in the irrigation pond. Is there no end to this madness?

(W. Rutland) Much of the vine crops and some corn are in but have run outta land to plant. Maggot trouble in the onions, I killed them with chemicals. Beets are coming slow. The only good thing is that the early corn I planted is looking great. Go figure.

(Norwich) Cold dark weather hard on greenhouse plants: Botrytis, leggy growth, and too many plants backed up waiting to go out in the field. Feel fortunate to have corn under plastic and row covers on first plantings, bare ground planting just coming up and yellow at that. Under covers is green and looks pretty good. On May 21 found numerous cabbage maggot fly eggs on Brassicas. Row covers really paying their way in everything this year: spuds, lettuce, cukes, greens, corn, etc., but everything is very late and now not growing at all, even the weeds look pretty sick and cold. Overwintered spinach, however, is beautiful and tasty!

(Planfield) This is a good spring for strawberries. The new planting is taking beautifully. The cloudy weather has kept frost away, and we are just seeing flower clusters above the ground.  Looks like July berries here. Scouting has shown no clipper or TPB yet, but they will show up
when the weather warms. We will be using a new, OMRI certified Beauvaria bassiana spray, Naturalis L, for TPB control this year.

(Starksboro) Each week the fields get dryer, only a few wet holes left. We could still use some sunny days, at least more than one a week. We have managed to keep planting largely on schedule. Potatoes and corn are up. Not much signs of TPB, which is kind of spooky, like a horror movie, because I know they're out there somewhere. Plant sales have been a bit slow compared to the last two years. But as I look back 3 and 4 years which were cool and wet in May, things are about on target for that type of season which is often stronger in June. I burned off the asparagus ferns this spring and I'm hoping this lessens the asparagus beetles. Waiting for the spirea bush to come into full bloom, a sign that the degree days have accumulated enough so that the cabbage maggots are just past. I'm using avoidance as a strategy so full bloom of the spirea bush indicates it's safe to put out cole crops without any need to spray or protect against maggot. It means, however that we don't have any cole crops much before August 1.

(Dummerston) Not as much activity as we'd like to see in the fields this week. We laid quite a bit of black plastic to trap the moisture to see us through dry weather that theoretically should come.  Tough to do any cultivation and weeds are emerging rapidly. Transplants and seeded crops doing well under plastic and remay, we even covered peas to push them along. Started picking greenhouse tomatoes, asparagus growing like crazy. Flower sales going strong despite the weather. If the sun comes out this weekend the cash registers will be singing. Might have to get a bigger wheel barrow.

(Grand Isle) Picked first of wintered over spinach. Seeded winter squash in greenhouse in 72 cell trays for second year in a row. Probably won't direct seed in field  any more. Finally got some beans and corn in. Trying the planting of corn seed in a shallow trench with covering of clear photodegradable plastic mulch. May 22 set cherry tomatoes out on black plastic.

(Amherst MA) It's wet down here. Lots of green growth on soil in the greenhouse starts. I think early cucurbit seeds are rotting in the ground, as is the early corn. I gambled for an early harvest and will have to replant. Still not complaining, as last year we were irrigating like crazy by now. The spinach is still small but the greens and lettuce are starting to pick up now. Lots of things just need a little bit of warmth. Flea beetle pressure is less with all of the rain. And no sign of cuke beetle or CPB yet. Potatoes emerging from the ground now 2 inches tall. Strawberry blossoms look very fine and berries are starting to form.

CUKE BEETLE CONTROL OPTIONS (adapted from MN Cooperative Extension)
A relatively new product which is less hazardous to pollinators than conventional insecticides is called Adios, a cucurbitacin bait that contains low levels of Sevin. The product contains Sevin encapsulated in a feeding stimulant, which induces Striped Cucumber Beetle (SCB) to feed on the Sevin but will not attract additional SCB into the field. The product is encapsulated and therefore is more difficult for pollinators to ingest while visiting flowers. Recent studies in Minnesota indicate Adios can be effective for low to moderate SCB infestations.
A new trap and lure have recently been developed by Trece, Inc., Salinas CA, for detection of SCB. The trap consists of a small plastic top that fits over a plastic cup. A "stun pill" is inside the trap and contains small amount of Carbaryl to kill SCB. On the outside of the trap is a lure that attracts SCB to the trap. Preliminary trials conducted in 1999 indicate that the traps are useful for early detection and may show promise as a control option for small acreage plantings (<1 acre) to trap out a significant portion of the population. These traps may be useful in organic production systems where few options are currently available for control of SCB.

BLUEBERRY MAGGOT MONITORING (from Michigan Extension)
Determining the onset of adult fly activity is essential to the control of blueberry maggot, as protective sprays must be applied before the 7 to 10 day pre-oviposition period ends. Adult files can be trapped on yellow sticky boards; the catch will be enhanced if the boards are baited with protein hydrolysate and ammonium acetate. Commercially available yellow sticky board traps for apple maggot adults can be used effectively. Traps most commonly used are yellow cardboard or plastic. These can be bent in half, sticky side down, to form a V pointing downward; traps can be suspended from angled stakes so that the bottom of the trap is 6 to 10 inches above the canopy. Place traps along field borders. Use at least three traps per field or one trap per acre. Set traps up in early June. Check traps twice per week, replacing sticky panels every 2 to 3 weeks. Traps should be placed on the perimeter of commercial fields, or just outside of commercial fields in abandoned or wild blueberries if these are nearby. Blueberry maggot adults generally do not enter managed fields until some time after emerging in wild areas; adults may have already passed through their pre-oviposition period by the time they appear in commercial fields. Traps in nearby wild areas will provide a more timely indication of maggot activity. Sustained catch of the blueberry maggot fly in traps indicates that it is an optimal time to make an insecticide treatment; sustained catch means not just the first one or two flies, but consistent catch of several flies per week. Once adult activity has been detected and the timing of the first protective spray determined, monitoring may be discontinued. Pesticide treatments must be continued on a regular schedule through the end of harvest in order to adequately protect the fruit from infestation by the blueberry maggot where this pest is a problem. (Be sure to use materials with appropriate days-to-harvest label.) Clean harvest and prompt picking may provide a small amount of control.

VERMONT HERB GROWERS ASSOCIATION
This association's mission is to network to cooperatively grow herbs and sustainably supply and expand the market, while engaging in education that nourishes people and environments. The association is sponsoring 3 farm tours for members this summer. For membership information contact Kathy Kinter at (802) 728-6205 or larrytho@together.net