Measuring harvest losses is a crucial step for growers to make informed decisions and adjust their combine settings to help collect as much yield as possible and minimize seed going back into the field.
Why Measure?
“Measuring losses is a small step that can help farmers make sure all their crop ends up in the bin and not back out in the field,” said Justine Cornelsen, Agronomic & Regulatory Services Manager for BrettYoung. “It’s not just the seed saved at harvest but the dollars saved in future crop years when trying to manage volunteer populations.”
Sometimes that little bit of seed going out of the back of the combine doesn’t look like much, but the dollars lost start to add up quickly. Different crops, varietal differences, and environmental conditions all call for different combine settings, so checking for losses several times while combining is an important practice to adopt.
How to Measure
To measure true losses, use a drop pan at the back of the combine after disengaging the spreader. Several drop pan setups can be used to collect a sample. Once collected, clear away straw and chaff so only seed remains.
Measure the seed in the pan using weight or volume. Then calculate the seed weight or volume based on one square foot and determine the concentration factor for your combine (the ratio of header width to combine discharge width). Use these numbers to get losses in pounds or bushels per acre with these tables: ccc_pami_combine_seed_loss_guide_2017
From there, it’s up to you to determine if the losses are acceptable. If not, change one combine setting at a time to see which adjustments help bring losses down.
Some Watch Outs
Changes in temperature, humidity, wind and field variability can drastically change the combine settings required to capture seed. Knowing your combine and adjusting throughout the day will make a large difference.
Canola pod shatter tolerance traits can be strong, and one common challenge is sending full pods out the back of the combine. In this case, the combine is under-threshing. Adjustments such as increasing cylinder or rotor speed, narrowing the concave setting, adding concave blanks, or slowing down can help crack those pods.
Header losses are not captured when measuring what exits the back of the combine. This is especially important when the crop is overly mature. Slowing down and adjusting reel speed can help reduce these types of losses.
Take the time to measure — it will save you time and money!
FAQ
Why is it important to measure harvest losses?
Measuring harvest losses helps growers make informed combine-setting adjustments to minimize crop left in the field, maximizing yield in both current and future years.
How should growers properly measure losses during harvest?
Use a drop pan at the back of the combine after disengaging the spreader. Clear away straw and chaff, then measure the remaining seed by weight or volume. Use size-based calculations and established loss tables to estimate losses per acre.
What factors can affect combine settings throughout the day?
Shifts in temperature, humidity, wind, and field variability can all impact combine performance, requiring adjustments to minimize losses.
Are all types of losses captured by measuring behind the combine?
No. Header losses are not captured when only checking what exits the back of the combine. Growers should monitor crop maturity and adjust ground and reel speed to help reduce those losses.
