Regional reports on Michigan vegetables – June 29, 2011
MSU Extension educators’ pest and vegetable updates for Michigan.
This week’s regional reports:
- Southwest Michigan – Ron Goldy
- East Michigan (Lapeer, Macomb, St. Clair) – Hannah Stevens
- Grand Rapids Area – Bill Steenwyk
- West Central Michigan – Norm Myers
Temperatures were near normal with highs from 69 to 83°F and lows from 59 to 65°F. There was less than 0.25 inches of rain for the week and only about 1 inch for the past two weeks, so some sites are getting dry and irrigation is being applied.
Transplanting is essentially done. Direct seeding of cucumbers, summer squash and sweet corn continues.
Peas, cucumbers and summer squash harvest continues with no problems. Direct-seeded summer squash is close to bloom and harvest from these fields would be expected next week.
Earliest potatoes are in bloom and all stages of Colorado potato beetles can be found.
Non-tunneled tomatoes are setting fruit. Stakes continue to be placed in fields and plants are being pruned and tied.
Peppers and eggplants are blooming. Some transplants were stressed in the transplant tray, flowered and the flower set fruit. These plants will have trouble reaching full size since they have the fruit on such a small plant. It would be good to remove that fruit if possible. Suspected bacterial spot was observed on peppers.
Tunnel-grown cantaloupes are in bloom and harvest will start soon. Watermelon is runnering off the plastic and is in bloom.
Pumpkins and fall squash are beginning to runner, so growers should make final cultivations and sidedress with fertilizer.
No squash vine borers or European corn borers were caught this week. Variegated cutworms averaged five per trap.
Thunderstorms brought variable amounts of rain to this area last week, including scattered hail. Cool temperatures in the 70s and low 80s and windy conditions prevailed. Many fields remain too wet to complete seeding and transplanting operations and warm season crops are in need of heat. The forecast predicts more favorable conditions. While some row covers have been removed, many still remain, particularly on vine crops.
European corn borer numbers, being monitored in one sweet corn field, are lower than last week, averaging 5.6 moths per trap. This number is over threshold if the corn is tasseling and I did observe first and second instar larvae feeding on leaves and emerging tassels of early corn. I also noticed a high number of tarnished plant bug adults feeding in the tassels. While they will not do damage in this crop, they will cause flower abortion and fruit deformation in other fruit and vegetable crops, so they bear watching.
While there is some cabbage harvest in the southern part of the region, the crop development in northern counties is behind average. Cool season crops on the retail market included fresh garlic and onions, lettuce, beets and even some cauliflower grown under row covers.
First generation Colorado potato beetle larvae are doing serious damage on potato foliage where controls have not been applied. Watermelon is vining and flowering, but there is a notable lack of honeybees in these and other fields. Pumpkin and winter squash seeding is on schedule on some farms and behind schedule in others.
The past seven to eight days have been wet and cool. Much of the region from southern Ottawa, Kent and Ionia counties to Van Buren County received 0.75 to 3 inches of rain in multiple events. However, central Ottawa County to southern Newaygo County received over 6 inches, with 5 inches or more on June 20 alone. Spotty hail storms destroyed some Ottawa County crops. The region has also been cool.
Last week, I announced that most of west central Michigan had finally surpassed the unusually cool 2009 growing season in terms of heat accumulation. That has changed. MSU Enviro-weather stations in Ottawa, Kent, Ionia, Allegan, Barry and Van Buren counties all report the cumulative, base-50 growing degree day accumulation as once again lagging behind that of 2009. Only the southern Newaygo County area (Fremont station), remains slightly above 2009.
Celery transplanting continues where soil moisture conditions permit field work. Crop maturity lags behind normal, but the fields appear to look good overall. There may be a few exceptions where recent rainfall was excessive
Onion conditions vary quite a bit. Some fields look good, while other stands have been badly thinned by excessive moisture, as shown in Photo 1. The need for timely, post-emergent herbicides in onions is evident in the Photo 2. It shows a test plot where only various preemergent treatments were used, as opposed to the surrounding field area, which received typical post-emergent herbicide applications.
Other muck crops, such as radishes, leeks, turnips and red beets appear to be fair to very good, depending on moisture conditions. Carrot stands vary, once again, depending on rainfall and field drainage.
A large, Ionia County pickle field experienced significant seeding death, especially in the lower and finer-textured areas. Lab tests haven’t confirmed it, but I suspect damping-off from continuous wet conditions (Photo 3).
Cabbage continues to be transplanted and some of the first harvest has been taken. Reports are positive overall. Tomatoes, peppers and squash appear to be healthy, but our recent wet weather may change that. Growers should keep a careful watch and apply protective fungicides as conditions warrant. Sweet corn looks OK, but needs more heat to spur growth. My southern Kent County European corn borer moth trap counts were low at two, two and three. Growers also report seeing only a few moths.
West Central Michigan
Temperatures have been generally below normal over the last week. We had a very long wetting period Thursday and Friday of last week (June 23-24), which may result in an upswing in disease in vegetable crops. The recent rains have taken care of any previous moisture deficits and no one is currently irrigating.
Asparagus production is still not complete. The majority of growers have finished harvest for the season, but at least two processors continue to receive asparagus and I am told that one of them plans to continue to do so for a couple more days. If so, that will be the latest finish to the harvest season that I can remember in all of my years working with this crop. On the pest front, common asparagus beetles are still pretty active, with mature larvae present in young fields where harvest finished early. Foliar diseases, purple spot and rust are present in new fern. Yesterday (June 28), I found my first rust uredospores, which are the rapidly spreading stage of the disease.
Vine crops are coming along well with a few thin stands, but a generally good crop. There is some striped cucumber beetle activity in earlier planted fields and a few leaf spots that look to be some kind of bacterial disease.
In carrots, I submitted another aster leafhopper sample yesterday. Numbers are still not large, but recent rains could have brought more migratory leafhoppers and I thought it was best to check the infectivity. I did find a sample of what looks to be Cercospora blight on carrots and it is worrying that we are finding it this early. Tom-Cast sensors are set, but I do not plan to read them until tomorrow (June 30).
Planting of processing broccoli continues. The earliest planted field is showing some flea beetle damage.
I caught only one European corn borer, but did catch two corn earworms and two western bean cutworms in my sweet corn insect traps. MSU Diagnostic Services got back to me on my sweet corn sample that I submitted last week and it did not have Stewart’s wilt. My current best guess on that sample is fertilizer burn.