TWILIGHT MEETING REMINDER
Wednesday May 22, 5-7 pm at Wood's Market Garden, Brandon on Route 7, 1½ miles south of Brandon and 15 miles north of Rutland. (See description in the previous newsletter.)
REPORTS FROM THE FIELD (as of May 14)
(W. Rutland) Plastic is laid and transplants are ready to go. Of course the weather is not so I have kept busy working the flowers and shooting woodchucks and crows. Crow season is over now but there seems to be a good supply of woodchucks. With a little luck the frost will stop and I can put my rifle down to get some transplants in.
(Plainfield, NH) Seeing some damage in strawberry buds emerging from crowns, suspect they took a hit back on April 26 when the temps took a nosedive into the very low 20's. Buds were still in crowns, but they evidently must have been susceptible. Plants now have buds emerging from crowns. Leaves on plants (not under row covers) are very small, almost stunted. Hoping that it's a response to the generally cold weather of late. Small stuff that was field-seeded is up, but we are irrigating to make that happen. Transplanted ½ acre of sweet corn at the insistence of one of my employees, no row cover on yet, hopefully tomorrow. Hoping this is as good as an idea as was touted in the winter meetings. Bedding plant sales a bit off to date, but it's early and the weather hasn't been real conducive to gardening. Come to think of it, it hasn't been too conducive for farming....
(Fairlee) This cold weather is throwing off planting schedules like I have never seen before. Plant sales are off by 50% from last year and 25 % in a normal year. I am seeing a lot of abscission of tomato blossoms in our greenhouse. I have had to replace about 40 tomato plants or 15% in another house which has black plastic. The symptoms are a girdling of the stem at the soil level. I guess either Botrytis stem rot or Sclerotinia. I will send a sample to the UVM Diagnostic Lab.
It's really bizarre to have seeded the earliest peas on record only to find the third crop needing to go in later than ever before. First lettuce planted a week earlier than planned was not very hardy because of warm weather in mid-April then devastated by 20 degree frost at the end of April. Flea beatles made an appearance only to quickly retreat in face of the impending snow. Definitely a year for lots of row covers--wish I had used more!
(Starksboro) Cool weather is making for a good old fashion Vermont spring. This is allowing us to keep up with the planting at a sane pace. Unfortunately bedding plant customers are feeling the lack of urgency as well. It is reassuring to get some significant rainfall, even though that means it's cool and wet. However, I am a firm believer in "the average season" where rainfall and temperature ultimately average out over the course of the season, though in the process of doing so each cool spell must be averaged by a hot spell an likewise wet with dry. I found an excellent publication with many potting mix recipes at: http://www.attra.org/attra-pub/PDF/potmix.pdf
(Dummerston) Good thing we invested in a load of irrigation equipment, it hasn't stopped raining since it arrived 2 weeks ago. The drought was tough on vegetable growing, but loved those sunny days for retail sales. Now garden center sales are on hold except for the hardcore plant shoppers. Greenhouses are full and need spacing to keep good air movement and discourage botrytis. On the bright side, lack of hot weather has kept down invasions of thrips, mites and aphids. Fields are ready to go, plants are ready to go, workers are ready to go, bring on the sun.
(Charlotte) We scrambled to get all sorts of Brassicas, the third round of lettuce and a bunch of odd CSA crops into the ground in the 3 day window of time when our lovely clay soil dried out enough to be workable. That's pretty much what happened about 3 weeks ago, and most of what was planted then is just sort of sitting under row cover not showing much forward progress. On the positive side, peas are up nicely, garlic is thriving and onions are coming up as well. Looks like there will be plenty of time in the next week to get tomatoes, peppers and eggplants into the greenhouses.
(New Haven) I've ended up with 600 more black currant plants than I need. The variety is Titania, which is white pine blister rust resistant. They're in my cooler, and I'll sell them for a dollar each. Chris Granstrom. 802-388-7368.
PREVENT SEED CORN MAGGOT DAMAGE
(adapted from fact sheet by Gordon Neilson, former UVM entomologist)
The yellowish-white seed corn maggot burrows into seeds in the soil, attacking many vegetable crops. It injures sprouting corn, but is much more likely to damage beans and peas. Cabbage, turnip, radish, onion, beet, spinach, and potatoes may also be attacked. Damage is greater in cold, wet weather and when the seed is deeply planted, as these conditions contribute to slow germination and emergence. Damage is less likely to occur on sandy soils.
The seed corn maggot passes the winter in the soil of infested fields in the maggot stage inside the last larval skin--a dark brown, capsule-like puparia about 2 inch long. Occasionally, maggots may over-winter in manure or about the roots of clovers. The first-generation adult flies emerge in early spring about planting time. These flies are grayish-brown to slightly greenish in color and about 1/5 inch long. The flies deposit their eggs in the soil where there is an abundance of decaying organic matter (such as manure), or on the seed or young, developing plant.
The hatching maggots make their way to the sprouting seeds where they bore into, feed on, and often destroy the cotyledons and growing point of the seed of young plants. The eggs hatch readily at temperatures as low as 50 degrees F. Larval and pupal development may continue at temperatures from the mid-50s on up. The full-grown maggots are 1/4 inch long, typically sharply pointed at head end, legless, and with a very tough skin, although they appear fragile. Pupation takes about 2 weeks. The life cycle can be completed in 3 weeks, and there are probably 3 generations per year in Vermont. It is the first that does the severe damage. The second and third generation appear in mid- and late summer.
Because the weather and seed corn maggot populations are very variable, take precautions every year to keep damage from this insect to a minimum. Otherwise, the seed corn maggot will probably not be detected until seeds and seedlings are lost. Then it is too late for effective control on the planting, and the field must either be replanted or left as a poorly developed stand. Control consists of preventing seed corn maggot damage through a combination of the following: Promote rapid germination and growth by planting as shallow as practical and waiting until the ground is warm. Plow heavily manured or cover-cropped land early the previous fall, so it will be less attractive to the egg laying flies the following spring. (By thoroughly mixing in organic matter to prepare the surface layers of the soil, you'll get more rapid germination. That, in addition to shallow planting, will reduce the damage, because the insect is attracted by humus and moisture.)
When possible delay planting until the first generation is pupating (probably early June). Reduce use of organic fertilizer in the seeded row, whenever possible. Reset or replant heavily damaged fields to get an adequate stand. Some crops have insecticides labeled for seed treatment or in-row treatment to protect against seed corn maggot (see the 2002-2003 New England Vegetable Management Guide).
Damage by other species of maggots is also favored by cool wet weather.
The onion maggot attacks onions by boring into the developing bulb causing
the plants to yellow and die (See: http://ctr.uvm.edu/ctr/el/el76.htm)
and cabbage maggots attack the roots of young cabbage, broccoli, etc.
STRAWBERRY LEAF SPOT
(adapted from article by C. Heidenreich and W.Turechek, Cornell Univ.)
Leaf spot (Mycosphaerella fragariae) is one of the most common and widespread diseases of strawberry. Symptoms vary with strawberry cultivar, strain of the fungus, and environmental conditions. Leaf spots lesions are small, round, 3 to 8 mm in diameter, dark purple to reddish, and found on the upper leaf surfaces. The center of the spots becomes tan to gray to almost white over time, while the margins remain dark purple. Lesion centers on younger leaves stay light brown, with a definite reddish purple to rusty brown margin. Numerous spots may coalesce and cause death of the leaf. Large, spreading lesions that involve large portions of the leaflet are formed on some highly susceptible cultivars; the centers of which remain light brown.
On leaf stems (petioles), runners, fruit stalks (pedicels), berry caps (calyxes) symptoms are almost identical to those on leaves. Only young tender plant parts are infected by this pathogen. Superficial black spots (6 mm in diameter) form on ripe berries under moist conditions. These spots surround groups of seeds (achenes) on the fruit surface. The surrounding tissue becomes brownish black, hard and leathery. The pulp beneath the infected area also becomes discolored, however, no general decay of the infected berry occurs. Usually only 1 or 2 spots occur on a berry but some may have as many as 8 to 10 "black-seeds" which are most conspicuous on white, unripe fruit and on ripe fruit of light colored cultivars.
In northern growing regions 3 sources of primary inoculum may be present: conidia overwintering on living leaves, conidia from overwintering sclerotia, and ascospores. Abundant conidia, produced in early summer on lesions on both upper and lower leaf surfaces and lesions on other plant parts, are spread primarily by water splash. High rainfall can lead to disease of epidemic proportions. Sclerotia are produced profusely during the winter on dead infected leaves. These may also produce abundant conidia in the spring. Conidia produced in leaf infections are probably the primary inoculum source for fruit infections.
Leaf spot may reach economic threshold levels, provided young leaves and inoculum are present, under conditions of high temperature and long period of leaf wetness. Research results show most severe infection of young leaves to occur during periods of leaf wetness from 12 to 96 hours, when temperatures fall in the range of 59-68 °F. This data suggests fungicide treatments should be applied in early spring, and after renovation of plantings if inoculum was present.
To minimize leaf spot, plant in well drained soil with good air circulation and exposure. Choose disease resistant cultivars. (a table of cultivars and their resistance to various diseases is at: http://www.nysaes.cornell.edu/pp/extension/tfabp/factshts/smallfr/stbapx.html)
Plant only disease free plants purchased from reliable nurseries. Apply
nitrogen fertilizers only at renovation to reduce succulent new leaf tissue
which is more susceptible. Carefully space runner plants in matted-row
culture and control weeds in all plantings to improve air circulation and
reduce drying time for leaves. Remove older or infected leaves before setting
runners in new plantings. Removing and burning all debris at renovation
(after harvest) helps to reduce overwintering inoculum of leaf pathogens.
If leaf diseases are a problem in the planting, follow a fungicide spray
schedule recommended for control of leaf diseases and fruit rots to aid
in control (see the 2000-2002 New England Small Fruit Management Guide).
Thoroughly cover all above ground plant parts with spray, especially undersides