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POSTED: June 5, 2014 3:00 p.m.
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There are a lot of fungi that can attack tomato plants.

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It is early June and time to apply mole cricket control. All the new hatch of mole crickets should be out by now. While they are hard to see and do not cause much lawn injury now, by late July and August I expect to be getting calls about dying patches in lawns.
By then the bugs will be too big and robust to control easily. A preemptive strike now while they are small and vulnerable will save control costs and loss of turf quality later.
Our recommendation for home lawns is a granular insecticide labeled for mole cricket control in home lawns. Usually these granular insecticides need to be watered in with irrigation or light rainfall fairly quickly after application to disperse the insecticide into a chemical barrier at the surface of the soil.
Always follow the directions on the label of the product you are using. The Label is the Law. There is nothing on a pesticide label that does not need to be there and nothing on the label that you can afford to ignore.
Even the best application will not provide 100 percent control. Ninety-five-percent control is considered excellent. Finding one or a couple mole crickets in the lawn a couple weeks later does not mean that you or your lawn care company did something wrong. Insects that are missed by a treatment are called escapes.
These escapes do not represent failure of the application. Some bugs may have tunneled outside the treatment area or stayed underground and somehow missed the treated soil. Maybe they came in from your neighbor’s lawn or flew in from farther away. The objective of pest control is not extermination of the species. The objective is to lower the severity of impact to a level we can tolerate.
If you had one mole cricket tunnel per square foot on average in your lawn this spring, then treat now with the granular. If you had less than that, the mole crickets you do have will not likely do enough injury to you lawn for you to notice — so no control is needed for now.  
If the numbers build up and you do see mole cricket injury to your lawn this summer, even if you applied a granular treatment this month, all is not lost. This autumn you can go after the larger adult mole crickets with a bait treatment in September or October.  
Tomato calls are starting to come in. I cannot be sure but we seem to have Gray Leaf Spot starting to show up. Three species of the Stemphylium fungus have been found to cause gray leaf spot. Both Early Blight caused by Alternaria species and gray leaf spot seem to work their way up the plant from the ground up, but Alternaria leaves targeted, ringed leaf spots while Stemphyllium does not.
I can get into the tall grass about the differences between and among Gray Leaf Spot, Early Blight, Late Blight, Gray Leaf Mold, Anthracnose, Septoria Leaf Spot and Botrytis on tomato but the main question from homeowners is “What to Spray?”
For all of these fungi on tomato leaves, chlorothalonil, which most of us know as Daconil for home use or Bravo for field crops, is the material of choice. However, knowing what species of fungis is causing the problem is also important because there are non-chemical methods we can use to control these diseases on home vegetables that are important not only in reducing chemical use but conserving the utility of our pesticides by not forcing the pest to develop resistance to the pesticide.
 If we can control Alternaria early blight by putting down a three-sheets-thick layer of newspaper under the mulch in the garden and water by drip irrigation we prevent the rain splash or irrigation splash that bounces the Alternaria out of the soil and onto the leaves to start the infection process.
If we keep humidity down in the plant canopy by planting with row spacings that favor good air movement we can largely avoid Botrytis problems. If we control solanaceous weeds in and around the garden and buy clean transplants we can side-step much of the gray leaf spot problems.
Pesticide chemistry is what we fall back on when our cultural controls fail. Employing cultural controls is generally more economical and reduces the introduction of poisons into the environment.
More importantly judicious use of pesticides conserves the usefulness of a pesticide by not putting so much pressure on the pest that it develops resistance and renders the chemistry impotent.

Gardner lives in Keller and is the UGA extension agent for Glynn County, serving South Bryan.

 

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