Heavy infestations of southern corn beetle can damage corn plants so extensively that they die. This pest can destroy corn seedlings down to the soil. In fact, even a healthy stand of corn can be destroyed when a large population of this insect lands in a field.
Begin scouting for southern corn leaf beetles as soon as seedlings emerge. A sign to note is that beetles easily fall to the ground when corn leaves are brushed by human movement through a field, but they are difficult to see because of their small size. A hand lens is helpful. Refer to a pest identification guide to avoid mistaking southern corn leaf beetle damage for cutworm or armyworm feeding. Follow University Extension weekly and monthly reports for scouting guidelines and economic thresholds for insecticide treatments in specific corn-growing geographies.
Southern Corn Leaf Beetle Management Options
In no-till or limited-till situations, southern corn leaf beetle may become established in the soil, overwinter and feed on newly planted seedlings. For best results managing southern corn leaf beetle, remove existing crop residue and control weeds through tillage, a burndown herbicide and residual preplant herbicides.
Taking out existing vegetation prior to planting will also provide better penetration of insecticide spray or granules. Season-long weed control helps prevent southern corn leaf beetle from causing crop damage and harming yields and will help improve effectiveness of in-season insecticide treatments. Additionally, crop rotation continues to be one of the most economical and effective cultural practices for controlling a wide range of crop pests.
Farmers should consult with their seed dealer and review University Extension field trials to evaluate corn hybrid options and traits to help control southern corn leaf beetle. Although there is no trait that controls southern corn leaf beetle, using hybrids that will help control other insect pests can decrease your odds of misidentifying another pest as responsible for feeding damage if southern corn leaf beetle is the true culprit.
The best approach to managing southern corn leaf beetle is prevention. Bayer offers season-long insect pest control options from insecticide/nematicide seed treatments to foliar insecticide products.*
While this insect may not be a significant pest every year, when a severe infestation does occur – and it can – farmers need to be ready. Seed treatment is a good risk management measure. Under low to moderate southern corn leaf beetle pressure, there are insecticide seed treatments labeled to protect against this pest.
The Bayer portfolio of seed treatment products offers some of the best seed-applied solutions, including seedling disease protection and early-season insect and nematode control, available on the market today.
Poncho®/VOTiVO® is an excellent seed treatment to help fight against southern corn leaf beetles and a large spectrum of other corn pests such as thrips, wireworm, seed corn maggots and white grubs, as well as large-spectrum protection against nematodes. Poncho 1250 + VOTiVO enhances the length of efficacy against many of the secondary insects that damage corn like black cutworm and adds billbug and corn rootworm protection under low-to-moderate pressure. Poncho, the systemic insecticidal component, is absorbed by new roots immediately, providing control of many critical early-season insect pests. VOTiVO, with its unique bacterial strain that lives and grows on young roots, creates a living barrier that prevents damage from all soilborne plant pathogenic nematodes. This dual protection results in healthier plant establishment and a more uniform crop, positively impacting yields.
Under heavy beetle pressure, seed treatments may not offer enough protection. That’s when good scouting will help to make the decision if an insecticide treatment may be warranted.
Baythroid® XL insecticide, a pyrethroid, performs on a broad spectrum of corn insect pests, with fast knockdown and long residual control. At-planting application is recommended; however, Baythroid XL can be used all season long. Application timing should be based on careful scouting and local economic thresholds. Follow IPM guidelines to effectively use postemergence insecticides as needed and manage insecticide resistance in combination with other control practices.
Visit our corn section to learn more about insect control options in corn, including Poncho/VOTiVO and Baythroid XL, or contact your local Bayer representative.
*Always read and follow label instructions. Not all products are registered for use in every state. Baythroid XL is a Restricted Use Pesticide.