VERMONT VEGETABLE AND BERRY NEWS, Sept. 15, 2001
Compiled by Vern Grubinger, University of Vermont Extension
(802) 257-7967 ext. 13 or vernon.grubinger@uvm.edu
www.uvm.edu/vtvegandberry

REPORTS FROM THE FIELD (as of Sept. 11)

(Dummerston) As the 2001 growing season slowly comes to an end, and the vegetable farmers ride their tractors off into the sunset spreading rye and vetch, there's still time to squeeze out a few bucks to lose on an Ameri-trade deal with a late planting of radishes, arugula, cilantro and spinach. If September temperatures are going to be in the 80s, might as well take advantage of global warming. The whiteflies in the fall tomato houses and the cabbage moths in the cole crops seem to enjoy the warmer temperatures, too. Call in the Encarsia wasps and B.t. spray. A dry year equals no corn earworm and corn borer counts are low, so corn picking is going well on heavier land. Fall crops are doing well thanks to good rains after nothing for seven weeks. Looks like an even bigger investment in drip tape next year. On the other hand, the home gardener's flowers are shot with the heat, so fall plant sales to fill in brown spaces are extremely strong. Prices are up, demand is strong. What's not to like?

(Plainfield) The big push is on to get root crops out of the ground. At this time of the season, I  kind of exhale since we no longer have to weed, transplant and harvest all at once, and things are at a stage of maturity where the risk level of spring is past - now you know if things are doing well or not and you can do a field inventory and know pretty well where you stand. Thereís light at the end of the tunnel, and you can see the slower pace of life ahead starting November 15th or whenever the snow starts flying - Iím not sure if thatís a carrot or a stick. The end-of-season burnout is offset a bit by the financial fruit of the season coming in.

(E. Montpelier) We got a little bit of rain recently but weíve had only 2 inches since the end of May. Iíve never run irrigation in September before. The sweet corn crop is fairly good because we irrigated, but it was pushed forward and really ripened early with all the 90 degree days. Itís hard to sell corn wholesale since thereís a glut. This year has been a very good tomato year, and all the vine crops have been good. I never had so many melons, with such wonderful flavor. Itís hard to put cover crops in now as itís difficult to get things to germinate when itís so dry.

(Little Compton RI) Seems like we have hit the doldrums! One calm fall day after another and no rain. Fall squashes are enjoying a slow steady death. On the other hand our fall spinach, lettuce and greens etc. are going down quickly. We had a blessed summer of regular rain showers that kept us in good stead even though we knew the ground moisture was drying up. Now week 5 without rain and it is clear just how dry it really was. We intentionally planted fall acorn squash on July 15th to see if we would get a crop. It has been very successful. The sugar pumpkins on the other hand needed more time and probably won't get their full color. This leads me to think that I can re-assess what I have to get in by June 15th (i.e. pumpkins and butternut) and what I can put in a little later successfully.

(Argyle, NY) Fall crops growing excellent with warmer weather, although back to full irrigation.  Tons of cabbage loopers. Storage onions best crop ever. This week we'll be planting the annual bed strawberry plants and starting to pick apples. With one new intern and another starting in 2 weeks, our work load should get easier. Paul is off crutches and learning to walk again! There are many lessons to be learned while farming, especially how wonderful farmers can be at lending a hand to a farmer in need! We have been blessed.

IRRIGATING FALL CROPS FOR FROST PROTECTION
(Adapted from NC State and GA Extension)

Protecting vegetable crops from that first frost or two can prolong harvest for days or weeks, and increase profits. An effective method of frost protection late in the growing season is overhead irrigation. Hey, youíve been irrigating just about all season long, so why stop now?

Irrigation can protect against frost because heat lost from the crop to the environment is replaced by heat that is released when the applied water changes to ice. Specifically, as 1 gram of water freezes, 80 calories of heat energy are released. As long as ice is being formed, this Ďlatent heat of fusioní will provide heat.

There are some risks involved with sprinkler irrigating to protect against frost. The first and most important is that if the irrigation rate is not adequate, the damage incurred will be more severe than if no protection had been provided. An inadequate irrigation rate means that too little water is being applied to freeze at a rate which will provide enough heat to protect the crop. The situation is made complex by another property of water, evaporative cooling. As 1 gram of water evaporates, 600 calories of heat energy are absorbed from the surrounding environment. When compared to the 80 calories released by freezing, it becomes apparent that more than 7 ½ times more water must be freezing than evaporating to provide a net heating effect. Otherwise, the process of evaporation will take heat from the crop. An ice-covered plant will cool below the temperature of a comparable dry plant if freezing stops and evaporation begins. Since wind promotes evaporative cooling, wind speeds above 5 mph limit the success of irrigation for frost protection.

Secondly, with overhead irrigation, ice buildup can cause plant breakage; and thirdly, over-watering can cause waterlogged soils and nutrient leaching problems. Lastly, at present, most systems are of fixed-rate design. They can only be turned on and off, and no variability exists for the irrigation rate. Thus, most systems are designed for the worst possible case. This means excess water is applied in most frosts, further increasing the problems of too much water on the crop.

If the capacity of the irrigation system is not sufficient to provide protection under the extreme conditions expected during the night, the system should NOT be turned on. In general, no system will provide protection in wind speeds greater than 5 mph for tree crops, 10 mph for low growing crops. A backup power source is essential. Once started, irrigation must continue until the ice is melting and loose. This usually occurs soon after the morning sun hits the trees. A power failure can be devastating due to the evaporative cooling effect.

Timely and complete coverage of the crop is required. The distance between sprinklers should be no more than 60 percent of the wetted diameter; place sprinklers no more than 50 percent of the sprinkler radius from the edge of the field. The nozzles should make at least one revolution per minute and should apply 0.12 to 0.15 inch of water per hour. Start sprinklers before the temperature drops to 32 degrees F (say 34 degrees F) and continue irrigating until the temperature rises and the ice begins to melt or until the wet-bulb temperature rises above 32 degrees F.

END OF YEAR WEED SCOUTING (from UMass Extension)
A quick scouting can alert you to problems that will be expensive to solve if they get out of control and can give you clues that will help you in designing your weed management program for next year. Identifying weeds can help you identify potential problems before they get out of hand, and can help you decide if you need to modify your weed control program. Weeds like yellow nutsedge, hedge bindweed, and quackgrass are spreading perennials, which have underground parts that enable them to spread throughout whole fields.  Because these weeds can be very damaging, and are very difficult to control, they are worth "nipping in the bud."  In addition, keep an eye out for annual weeds which are new to your field or increasing in numbers.  Some weeds can be very difficult to control in some or all of the crops in your rotation. Galinsoga, for example, is hard to control in cole crops, peppers, and squash.  Nightshades are difficult to control in tomatoes for growers who rely on herbicides for control, because they are in the same family as tomatoes. Velvetleaf is hard to control in sweet corn. Spot treatment with Round-up, or hand pulling or hoeing, is worthwhile to eradicate small patches of particularly threatening weeds.

If some weeds are generally escaping, identify them.  They may point to weaknesses in your herbicide or cultivation program.  If mostly grasses, or mostly broadleaves are escaping, it may mean you need to adjust either the rates or the timing of your grass or broadleaf herbicides. You may also find the New England Vegetable Management Guide useful. This manual contains a chart listing the effectiveness of vegetable herbicides on most of the common weeds in New England.

Weeds in the rows or planting holes are much more damaging to crop yields than between-row weeds.  Weeds in rows may be an indication that cultivation equipment needs adjustment, or cultivation needs to be done earlier. Mapping weedy spots, and keeping some kind of permanent record of weed surveys, can help you evaluate your weed management over the years.

Once crop harvest and weed scouting is compete, disk or till the fields to destroy existing annual weed growth and to reduce or prevent weed seed dispersal.  If perennial weeds such as bindweed or quackgrass are present, consider an application of Roundup before cold weather arrives.  Time spent on these tasks now will greatly improve your level of weed management next season.

PLASTICULTURE AND HIGH TUNNELS SHORT COURSE
Co-sponsored by Penn State and Rutgers Cooperative Extension and the American
Society of Plasticulture. The program will be held in Clayton, (southern) NJ on October 24 and 25, 2001. Registration is $60 for one day, $100 for both days. For more information contact Michele Infante-Casella of Rutgers Extension at 856-307-6450 or minfante@aesop.rutgers.edu

NEW ENGLAND VEGETABLE AND BERRY CONFERENCE AND TRADE SHOW
December 11,12,13 at the Sturbridge Host Hotel in Sturbridge, MA. Featuring 100 trade show exhibitors, and 120 educational presentations. Complete program brochure with speakers and talk titles should be available next month. Here is the schedule of sessions:

Tuesday, Dec.11:  Strawberries, Cole Crops, Tomato, Weed Management, Labor, Biotechnology, Trickle Irrigation. Wednesday, Dec.12 : Blueberries, Peppers, Sweet Corn, Bedding Plants, Greenhouse Tomato, Brambles, Cover Crops. Thursday, Dec.13: Cucurbits, Fall Ornamentals, Alliums, Lettuce and Greens, Cut Flowers, Food Safety, Biocontrols, Organic Production

VERMONT VEGETABLE AND BERRY GROWERS ANNUAL MEETING
February 19, 2002, Rutland Holiday Inn.

NEW ENGLAND FARM DIRECT MARKETING CONFERENCE AND TRADE SHOW
March 14, 2002, Holiday Inn Boxborough Woods, Boxborough, Mass. Contact: Jonathan Bates, (413) 529-9232.