Multiyear Research Pinpoints a Key Factor in Harvest Yield Loss

Stalk Variability & Harvest Loss

We know that sixty percent of yield loss during harvest occurs at the corn head. But how?   

A multiyear study found that stalk variability increased with yield, especially in 200-bu. and higher yield environments. 

“Multiyear, on-farm harvest research confirmed a direct correlation between stalk variability and yield,” says Dustin Bollig, farmer and vice president of sales and marketing for Drago. “And it isn’t what most people think: as yield increases, so does variability.”   

Along with ear bounce, studies have shown that deck plate gaps as small as 1/8 inch between plants and plates can result in a one to four bushel per acre loss. * 

“Your best fields have the highest potential kernel loss.”  

To substantiate this claim, Drago conducted three years of field research, attaching electronic sensors from Headsight® Harvesting Solutions** to the self-adjusting deck plates of a Drago corn head. The highly sensitive sensors measured the number and extent of gap adjustments made during harvest.   

“Over the course of the three-year study, we uncovered more and more eye-opening data about how extensive stalk variability is within a given field,” Bollig explains. “We continued to refine our research over its course to validate the results.” 

The study has consistently demonstrated that row-to-row deck plate gaps differ by 1/8 inch or more nearly 90% of the time. In higher-yielding areas, row-to-row deck plate gaps vary by 1/4 inch or more 40% of the time.  

GAP DIFFERENCE BASED ON YIELD

DECK PLATE ADJUSTMENTS/ACRE  

Drago’s 2020 research revealed that its deck plates were making nearly two adjustments of 1/2 inch every second and 47 adjustments of 1/8 inch every second across the corn head.  

“What we’ve seen is that the automatic self-adjusting deck plates deliver a significant improvement to manage gaps and capture more yield at harvest,” Bollig says. “Often, gap size differences were significant enough that a single deck plate setting across all rows of the corn head could result in small ear loss, let alone kernel loss.”   

Hydraulic vs. Automatic Deck Plates

[2021] Drago has long described the yield-saving benefits of its automatic self-adjusting deck plates for minimizing gaps compared to operator-controlled hydraulic plates. The question has been: How significant is the advantage?  

[2021] Working with HeadSight,®** an independent manufacturer of header height control systems, we measured and analyzed deck plate movement. Sensors on the corn head counted a total of nearly 163 adjustments per row per minute.   

On a per-acre basis, the automatic deck plates made nearly 5,390 adjustments involving movements from 1/8” or wider, including 1,582 adjustments of 1/4” or more, and 196 adjustments of 1/2” or greater.   

“Keep in mind that the threshold for deck plate yield loss starts at 1/8”, and each row unit averaged 606 independent adjustments per acre involving that and more,” Bollig says. “The data also showed how both the left and the right deck plate of each row unit on the Drago GT worked in unison to minimize gaps.” 

ELIMINATING ROOM FOR ERROR

“The ability to manually adjust deck plates has led to a false sense of their performance for capturing yield. The study confirmed the value of automatic self-adjusting deck plates for minimizing gaps and capturing yield every minute and in every row across the corn head is working,” Bollig says. 

“Today’s farmers have too many distractions in the combine with too much variability in the field to adequately manage their deck plates, and it’s costing them yield,” he adds.  

Compare Fig. 1 and Fig. 2

Notice how both deck plates move equally, corresponding to changes in yield.

FIGURE 1: COMBINE YIELD MONITOR REPORT

FIGURE 2: DRAGO LEFT AND RIGHT DECK PLATE MOVEMENT, ROW UNIT 2

FIGURE 3: DRAGO DECK PLATE ADJUSTMENTS

FIGURE 4: DRAGO DECK PLATE SPACING AS A PERCENTAGE OF TOTAL TIME