As you have seen on the blog over the last month, we have reported Northern Corn Leaf Blight and Northern Corn Leaf Spot that has been found in the area. These diseases are typically found heavier in fields that are corn behind corn and good leaf moisture into the day. This year neither of these diseases has been a major player in our area, however the game changer has arrived a little early. Southern Corn Rust has been found in several Southwest Georgia counties and has the potential to spread rapidly with favorable conditions. Because of the severity of this pathogen, it is recommended that we protect our corn with fungicides. Below are some fungicide recommendations from Dr. Bob Kemerait, UGA Cooperative Extension Plant Pathologist.
Triazole fungicides (like tebuconazole) are effective against rust (but lack the broader activity against northern corn leaf blight) and have a two week protective window. Strobilurin products and combination strobilurin/triazole or strobilurin/SDHI (Priaxor) have 3 week protective intervals and also a broader spectrum of activity.
Here is a link to the Field Corn Disease Control section of the UGA Georgia Pest Management Handbook.
Of another concern is the presence of stink bugs in many of our fields. Lots are moving from wheat fields that are being cut and others are just migrating from weeds in field borders. I recommend that we scout for their presence and include an insecticide with our fungicide spray. Be sure to check for tank mix compatibility with a jar test before mixing these chemicals in your sprayer or crop duster. If you are seeking to control brown stink bugs it is recommended that you use a product with the active ingredient, bifenthrin as brown stink bugs have some resistance to other low level pyrethroids.
Here is a link to the Field Corn Insect Control section on stink bug control of the UGA Georgia Pest Management Handbook.
For more information contact your local County Extension Agent.