The majority of corn in Dooly County should be between V1 and V3 stage.
At this growth stage, there are a few things that we want to focus on.
Disease – Fortunately, if your corn is already planted, you are ahead of the game on disease. Corn planted in March or early April is less likely to be severely affected by disease than corn planted later. Although the best time for a fungicide application to manage southern corn leaf blight isn’t until the V8-V10 stage, now is a good time to start thinking about it. Shorter corn rotations, planting susceptible corn varieties, plentiful moisture, and a later planting date are all factors that could lead to a fungicide program being more beneficial. All corn growers who produce their crop under irrigation (or when rainfall is plentiful) should recognize the potential benefits from protecting their crop with a fungicide program. Though UGA Extension recommendations do not call for a blanket fungicide application on every field of corn in the state, it is recommended that all corn growers consider the opportunity for such. Think of fungicides on early planted corn as insurance, and on late planted corn as an investment.
Insects – There’s not much to focus on with insects this early in the season. Insect control in seedling stage corn is primarily conducted by your varieties’ Bt traits and your seed treatment or at-plant insecticide application. It is important to check your corn at this stage for insects and/or plant damage. If insects are present, heavy damage to the young seedlings can occur in 2 to 3 days if not controlled.
Weed control – Most corn fields that we have seen in Dooly County look pretty clean at roughly 28 days after planting. If you have started with a clean field, then you are already moving in the right direction. This early in the season it is important to remember that there is still time to plan on making herbicide applications over the top. Remember that different herbicides can be used for broadcast applications at different growth stages.
I apologize that this table is a little busy, but it is a good tool to use for making herbicide selections throughout the season.
Table 1. Times of Application/PHI for Postemergence Herbicide Labeled for Use in Field.
|Herbicide||Field Corn Stage of Growth||PHI(DAYS)||Grazing, Feed, Forage, Hay, Silage Interval (days)|
|Accent Q||1-2 leaf||20” or V620-36” or V10 – drops||30|
|Aim||spike||V8V8-14 leaf collars – drops||14 leaf collars||14|
|Callisto||pre||30” tall or 8 leaf stage||45||45|
|Clarity||1-2 leaf||5th leaf or 8” tall8-36” tall drops|
|Dual Magnum||PPI/PRE||40” tall||30|
|ET||Spike||V4V4-V8 – drops||90||50|
|Halex GT||Spike||30” or V8||45||45|
|Liberty||spike||24” or V724-36” – drops||70||60|
|Prowl H20||spike||30” or V8||21|
|Realm Q||1-2 leaf||20” or V7||70||45|
|Resolve Q||1-2 leaf||20” or V7||30|
|Roundup||spike||30” or V830-48” – drops||50||50|
|Status||V2||5th leaf or 8”8-36” or V10 – drops||72||32|
|Steadfast Q||1-2 leaf||20” or V6||30|
|Warrant||spike||24”24-30” – drops||40|
1NL = none specifically listed on the label.
Also keep in mind that certain formulations of glyphosate are not currently labeled for use on RR corn hybrids. Corn growers should check with their seed salesman to determine if their planted hybrids are RR or RR2 before making a POST application of glyphosate.The following is a summary of various glyphosate products that can be used on glyphosate-tolerant corn hybrids:
|Glyphosate Formulation||Manufacturer||Product Rate/A (ozs)||RR Corn Hybrids||RR2 Corn Hybrids|
|0.75 lb ae||1.12 lb ae|
|Credit 41 Extra||NuFarm||32||48||Yes||Yes (?)*|
|Gly Star Plus||Albaugh||32||48||Yes||Yes|
|Gly-4 Plus||UCPA||32||48||Yes||Yes (?)*|
*These generic labels make no specific distinction between RR and RR2 hybrids.
Thanks to Dr. Eric Prostko for the charts used in this post.
If you have any questions concerning your corn crop, please contact the Dooly County Extension office.