What is in this article?:
- Southern summer vegetables targeted by many insects
- Prevention best strategy in organics
- Vegetable production in Alabama is always at a high risk to insect damage.
- Insect pests range from caterpillars and true bugs that devastate our summer crop to the insects of cool-season crops like aphids and yellow-margined leaf beetles.
- Prevention in the best strategy in organic production.
Vegetable production in Alabama is always at a high risk of insect damage. Insect pests range from caterpillars and true bugs that devastate summer crops to the insects of cool-season crops like aphids and yellow-margined leaf beetles.
Warm winter temperatures and high humidity are favorable to the year-round pest activity. Conventional vegetable producers in the Deep South should get a copy of the 2014 SE Vegetable Crop Handbook for complete insecticide recommendations or contact their county Extension office. Organic producers and home gardeners should use the new Extension bulletins. Identify insect pests correctly then think about managing them using integrated pest management (IPM) tactics.
Conventional vegetable insecticides fall in 18 different categories. Caterpillars can devastate plant stands if not controlled. There are many effective insecticides for caterpillars with new modes of action. We have evaluated spinetoram (Radiant) and flubendiamide in our test plots as stand-alone or rotation products. These insecticides are more selective than synthetic pyrethroids and also are softer on beneficial insects.
Repeated synthetic pyrethroid treatments (like bifenthrin) can flare up spider mites in hot weather, so reduce your insecticide applications in unfavorable conditions or shift to selective products.
Certain insecticides like chlorantraniliprole (Coragen) and imidacloprid (Admire) can be applied through drip irrigation for early season insect control with long residual. Through a series of demonstration plots at research stations and commercial fields, we have shown that a mixed trap cropping system with Peredovik sunflower and NK300 sorghum can deter leaffooted bug feeding during mid to late summers. Two applications of insecticides like zeta-cypermethrin (Mustang Max) and lambda-cyhalothrin (Warrior) on NK-300 sorghum head reduced 70 to 90 percent leaffooted bugs without the need for treating the main crop against that pest.
Spider mite outbreaks were common across Alabama, and mowing grass close to the crop during hot weather results in greater spread of this pest. High-tunnel producers may also experience spider mites due to the lack of rainfall inside the structure.
Effective miticides include abamectin (Agri-Mek – also kills Colorado potato beetles), bifenazate (Acramite ), and fenpyroximate (Portal – a new product). For squash bug control, bifenthin (Brigade) and dinotefuran (Venom) provided consistent results in field tests. Apply insecticides timely when insects are most vulnerable, use a surfactant as recommended, and follow the pre-harvest interval mentioned on the insecticide labels before using the products. Rotate insecticides and minimize applications to conserve the natural enemies and pollinators.