East Michigan vegetable regional report – August 17, 2016
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EmailMuch needed rain events softened ground, but some field operations have been delayed.
Weather
The region averaged about 3.5 inches of rain over the last week. Most of it came between Friday and Sunday, Aug. 12-14, and was gentle. I haven’t seen any washouts, but there is a lot of standing water out there, and the heavier soils in our region will take a while to dry out. This has delayed some harvests and other field operations. Aerial applicators are flying on fungicides across the region, but they haven’t found out how to harvest that way.
The table below shows rainfall (inches since April 1) and degree-day (base 50 degrees Fahrenheit since March 1) accumulations to date from Michigan State University Enviro-weather stations in the region.
Rainfall and degree-day amounts in East Michigan as of Aug. 17, 2016 | ||||
|---|---|---|---|---|
|
Location |
Degree-days (+ added from last week) |
Five-year average |
Rainfall (+ added from last week) |
Five-year average |
|
2,014 (+201) |
1,873.9 |
13.31 (+3.82) |
14.63 |
|
|
2,033 (+188) |
1,877.6 |
10.86 (+3.87) |
14.83 |
|
|
2,081 (+191) |
1,923.3 |
11.56 (+3.69) |
14.33 |
|
|
2,014 (+185) |
1,904.4 |
10.17 (+2.79) |
16.67 |
|
|
2,034 (+193) |
1,909.2 |
11.66 (+2.39) |
16.00 |
|
|
1,887 (+186) |
1,803.7 |
12.60 (+4.14) |
16.76 |
|
|
2,028 (+188) |
1,924.8 |
10.68 (+3.16) |
13.78 |
|
|
2,149 (+205) |
1,952.9 |
12.32 (+3.78) |
15.12 |
|
|
1,918 (+192) |
1,812.3 |
17.76 (+4.84) |
14.80 |
|
Crops
All sweet corn pests are active right now. Corn earworm pressure has increased on the west side of the state, and the southwesterly weather patterns that brought the rain have probably brought more in. MSU Extension reminds growers that sprays should target green silks for these pests.
European corn borers, fall armyworms and western bean cutworms are also active in fields. These will all bore into stalks and corn ears, and sprays should target leaves and whorls that are still at pre-tassel to protect the pollen-bearing organ and growing tip of the plant. Some growers use air blast sprayers to attain good coverage, while others use tall sprayers with drop nozzles to hit silks paired with boom nozzles to spray over top. In warmer weather, the spray schedule should tighten up closer to three to five days.
Canning tomatoes are ripening quicker than expected. I have been seeing some stink bug damage. Unfortunately, the bugs themselves are harder to find than their damage. The most common species spends the first half of the summer on wheat before switching to tomato or soybeans in July. They tend to feed on green fruit, and their straw-like mouths leave wounds that turn cloudy yellow or white on the skin of red fruit. This is sometimes called starbursting. The damage can also extend a fraction of an inch below the skin as well, with a white, frothy pattern. According to “Stink Bug Management on Tomatoes” by Ohio State University, Warrior, Baythroid or Thiodan work well against them if 1 percent of fruit are damaged in July and early August.
Stink bug damage on tomato.
Green beans in the Thumb area were all harvested last week. Yields were around 4 tons per acre on the unirrigated organic ground. The Central Produce representative reported that 6 tons per acre yields were more common on irrigated and conventional ground towards central and western Michigan.
All peppers are being harvested now. Quality and size are good.
Most fresh market potatoes are reaching 4 inches in diameter.
Multiple foliar diseases in hard squash and pumpkins have moved in, and I have sent samples to MSU Diagnostic Services to identify them. In addition, I found my first patch of ripe pumpkins last week. That is exceptionally early. If the plants are losing their leaves, then you must protect them from sunburn by harvesting those pumpkins and keeping them in the barn until you are ready to market your Halloween products. Hopefully, they will hold.
It is also important to stay up on your powdery mildew control to maintain healthy handles until harvest. Here is the spray program that worked the best in Beth Gugino’s 2015 trial in Pennsylvania, and was presented at the Great Lakes EXPO December 2015:
- First spray: Quintec 2.08SC 6 ounces per acre (3 day PHI) + Bravo Weatherstik 6SC 2 pints per acre (0-day PHI) + Induce surfactant.
- Second spray: Procure 480SC 8 ounces per acre (0 day PHI) + Bravo Weatherstik 6SC 2 pints per acre (0-day PHI) + Induce surfactant.
- Third spray: Quintec 2.08SC 6 ounces per acre (3 day PHI) + Bravo Weatherstik 6SC 2 pints per acre (0-day PHI) + Induce surfactant + Vivando 2.5SC 15.4 ounces (0 day PHI) + Bravo Weather Stik 6SC 2.0 pints + Silwet L-77 surfactant.
- Fourth spray: Procure 480SC 8 ounces per acre (0 day PHI) + Bravo Weatherstik 6SC 2 pints per acre (0-day PHI) + Induce surfactant.
- Fifth spray: Vivando 2.5SC 15.4 ounces (0 day PHI) + Bravo Weather Stik 6SC 2.0 pints + Silwet L-77 surfactant.
Currently, Vivando requires a supplemental label for use on vine crops. Torino, Fontelis, Mettle and Pristine were substituted in the rotation in some of the treatments and control was still good. Those and Rally are adequate alternatives.
Melons are ripening quickly, and one grower reported leaving 50 percent in the field last week because of a lack of time, labor and plan to market that many at once.
Watermelons on unirrigated farms were experiencing mid-day wilting from the high heat and low soil moisture conditions. One grower reported the leaves drooping 6 inches or more and allowing for extensive sunburn on the fruit, and reducing yields by as much as 50 percent.
Special events
MSU’s Dan Brainard is hosting an in-row cultivation workshop in Milan, Michigan, on Sept. 8 at Zilke Farms. Contact Dan at brainar9@msu.edu or Vicki Morrone at sorrone@msu.edu for details.
Reserve your hotel early for the Great Lakes EXPO in Grand Rapids, Michigan, Dec. 6-8! Registration is not open yet, but hotels often fill up before then. Anyone can access educational session summaries from the Great Lakes EXPO at the website. View the session summaries.
Please contact me at phill406@msu.edu or 616-901-7513 to grab any suspected disease samples from your farm, or send the diseased plant parts to MSU Diagnostic Services.
