When insects, diseases, or weather events strike crops they get noticed.  You can see hail damage, you can calculate the damage thresholds for insects, and yield monitors will easily capture the impact of crop disease.  But what about the yield losses that are just as significant but harder to pin down?  Invisible yield losses are a huge source of decreased yields for our farmers; Bluewater Agromart is committed to working with our customers to stop this loss and to increase their yields.

Losses at Planting
We have been taught for years that if you don’t have your corn in the ground by May 5 in Bruce County that you will lose yield for every day afterwards that you delay planting.  This is false. Yes, if you can’t get it in you may have to switch to a shorter season variety or as a worst case scenario have to switch to beans.  But the greatest losses we see are not connected to the date, but rather the conditions at planting and the planting operation itself.  Corn planted into ideal conditions on the 15th of May can still out-yield corn planted into cold wet conditions on the 1st, or for that matter any less than ideal conditions earlier.  

Early planted corn is more likely to experience a loss due to weather stress and is more likely to be planted into wet soil, which in turn makes it less able to develop a good root system to protect it from summer stress events. Invisible yield losses for the most part are very difficult to pin down but have been observed many times in field experiments.  Every single thing that holds a crop back in the spring, from mucked in seed, to a frost event will affect the yield long after the planting season has passed.

Planter setup can also result in invisible yield losses.  Planters that rattle, ride too high or low, or have worn parts won’t drop seeds properly and this will result in losses.  Seeds that are skips are lost yield, and seeds that fall as doubles go through their maturity behind the rest of the crops, pollinating late and producing smaller wetter cobs that act as disease incubators, which lower yields and quality and increase drying costs.  

Planting too shallow will increase lodging and planting too deep will slow the plant down during its early life, even the distance between plants, the moisture of the soil that falls back into the trench, and the firming of the trench all affect yields.  All of these yield losses put together can be dramatic and unless you are looking for it are completely invisible, and a very good reason to calibrate planters in the spring and plant slowly.

Optimum Harvest Date
While many believe that they have a deadline to plant by, many also believe that the only deadline that exists in the fall is the point where it starts to snow and stick on the ground.  There is not a fixed plant by date, but believe it or not there is a harvest by one.  The problem is this date is different for every field, variety, and varies from year to year.  

The optimum harvest date for yield occurs at the point where crop yield is no longer generating and now yield can only be lost.  Yield lost after this point can be very significant, but it’s often discounted or invisible.  At this point the crop will be too wet to harvest, so we wait for it to dry down and aim to harvest at the economic harvest date.  

Numerous studies have found what many farmers already believed, that dry yield does disappear as corn dries from 30% down to 18%.  This yield loss is more than just the lost water and is another reason to do the math on drying bills before waiting to harvest at a lower moisture.  Often times the money gained by avoiding the phantom yield loss will more than justify the increased drying bill and creates another incentive to harvest corn early. 

Remember the yield can only go down after the crop is physiologically mature, and the longer the crop sits in the field drying the more likely it is a weather event will take it out.  ALSO the entire time it’s sitting there the plant is dead and decomposing from the stalk up, making it even more likely that a weather event will be able to inflict maximum damage.  Even without a weather event, every day that goes by, yield is decreasing.   At some point the yield you will have lost from phantom losses, general degrading of the crop or the downgrade in quality received will have paid for the drying.  

The Conclusion
Even though invisible yield losses are a depressing thought and we would probably be happier not knowing about it, it also represents a tremendous opportunity.  This is because once we understand where the yield is going it’s not invisible anymore.  We can solve the causes and capture the yield and the best part is that most of the changes are small or related to timing and require little or no new investments. ​


Click the following to be directed to the website:
High-Moisture Harvest Captures More Yield – Farm Futures
Kernel Dry Weight Loss During Post-Maturity Drydown Intervals in Corn - Purdue

Phantom Yield Loss