Fungicides

So far, the problem has been confirmed in four states. Agronomists are encouraging farmers to scout crops, estimate yield impacts in affected fields and determine whether to make adjustments to marketing plans.

Many early-planted soybeans in the Midwest are in the R2 to R3 growth stages now, ideal treatment timing for most disease issues. Agronomists offer three reminders to help you make the call — plus a fourth tip on herbicide rescue treatments.

Farmers and aerial applicators tell Randy Dowdy and David Hula some of the key considerations for effective fungicide applications are timing, droplet size and product reach in the crop canopy.

Unlike most leaf diseases, tar spot starts impacting the crop at the bottom of plants. That means fungicides you apply must penetrate and get deep into the crop canopy to provide effective treatment. If you opt to not treat the disease, consider making plans to harvest early and pre-booking some dryer gas.

With product and application costs totaling between $30 and $40 per acre, farmers will be taking a harder look at where they make the investment this season.

David Hula believes a high-quality carrier is so critical to the performance of his crop protection products that he loads and hauls all the water to the local airport that his aerial applicator uses.

Now’s the time to be scouting for the disease, especially where the inoculum is present. Tracking weather data, particularly daily humidity levels, can help you keep an eye on tar spot this season.

Alex Harrell, soybean world record holder, says the technology helps him make more accurate and timely foliar product applications, while costing less than using a ground rig or an airplane.

Corteva Forcivo will feature three modes of action to address foliar diseases in corn, soybeans, wheat and other crops via overlapping preventive and curative activity.

Despite being outside the optimum window for tar spot control, this Wisconsin field trial yielded strong results.