Corn disease impacts stalk quality and kernel and ear size, putting valuable yield at risk during harvest.

In a crop year already defined by high input costs and low grain prices, corn disease also posed a threat to farmers’ yield and overall bottom line during the 2025 harvest season. Specifically, southern rust and tar spot both showed up on Midwest farms this past July about a month earlier than usual in some parts of the Corn Belt. Many farmers found that the corn disease they faced during the growing season had lasting impact into harvest in the form of down and lodged corn.   

Corn disease impact

It’s important to know how corn disease impacts different parts of the plant. Both southern rust and tar spot are fungal corn diseases that attack leaves, thereby interfering with photosynthesis. Once infected, a corn plant will often produce smaller kernels, with the potential to reduce yields by as much as 45%.

Infected plants then tend to take extra sugars from their stalks and roots to fill grain, leading to weaker stalks more prone to lodging. This combination of down corn and smaller kernels requires adjustment of combine settings and a corn header designed to reduce yield loss.

“Even with fungicide, which did help preserve overall yield potential, we saw compromised stalks on our own acres this year, leading to down corn scattered throughout,” says Dustin Bollig, farmer and Dragotec vice president of sales and marketing.

Luckily, harvest equipment can make a huge difference in salvaging plants weakened by corn disease.

Maximize yield in weaker plants

Drago helps growers preserve yield – even in infected plants – with a head designed to salvage down and weakened stalks. With the industry’s lowest header profile, Drago corn heads are able to slip under stalks and catch dropping ears with less bounce loss out the front. Aggressive, overlapping gathering chains placed out front, in front of knife rollers, also pull stalks up and in to gather corn in less-than-ideal conditions.

Bollig adds that automatic self-adjusting deck plates on Drago corn heads also eliminate second-guessing the stalk size that must be done with manually operated hydraulic deck plates. “With our deck plates, producers don’t need to worry about pushing stalks over or losing small ears with misadjusted plates.”

Each Drago corn head is also available with optional long or short downed-corn augers, designed to ensure stalks are centered over knife rollers to prohibit ear loss over header sides. Plus, spring-loaded snouts work to keep stalks where they belong, using driver-adjusted down-pressure to make sure snouts stay under down corn. These features and more make a Drago corn head superior for capturing down corn. 

Besides having the right corn head to capture every kernel, growers can optimize timing and corn combine settings to ensure no yield is left in the field, including:

• Starting with any down areas to minimize ear loss
• If operating with hydraulic deck plates, set them only slightly wider than corn stalks
• Adjust how you drive, moving against the grain of the stalks

Review the full list of reminders.

Aiming to harvest grain at a higher moisture (over 17%) has also been shown to reduce kernel loss from shattering. However, higher corn moisture leads to heavier ears, which will tend to bounce more.

“The slower, rotating roller knives and QuadSuspension™ on Drago GT corn heads reduce ear bounce in addition to butt shelling,” says Bollig. The kernel capture technology within every Drago corn head, coupled with harvest best practices, is designed to give growers more yield and greater ROI in standing and down corn.

Enter every harvest with confidence

The industry’s most efficient yield technology helps Drago growers come out on top – even in unfavorable harvest conditions. And, as important as it is to take learnings from the season behind, focusing on what to do now to benefit future harvests can make a huge difference in ROI.

During the off-season, Bollig recommends corn growers weigh the cost of repairs versus replacement. “Downtime, especially in diseased corn, can be detrimental to capturing yield at the ideal time and moisture level.”

Investing in the right solutions now can save immense time and money down the line. Keep your corn header performing at peak efficiency to achieve powerful results, starting with following Drago guidance and using Drago certified parts.

“It really does pay to keep your Drago all Drago,” says Bollig. “For all the advantages Drago corn heads provide, research has shown they function their best when maintained with Drago certified parts.”

Every Drago owner also has access to Drago Club for exclusive service and maintenance videos, manuals and more.

Whatever each crop year brings, Harvest Like You Mean It with Drago.