Now Reading: Early Harvest: Gathering Your Crops – And Data – Ahead Of Schedule

Early Harvest: Gathering Your Crops – And Data – Ahead Of Schedule

by Luke Cole, Manager of the Climate Research Farm in New Berlin, IL

August 30, 2018


The rumors are true: harvest will come early this year across much of the Midwest! According to USDA crop progress reports,* corn and most crops are in advanced maturity stages and will be ready for harvest at least 10 days to two weeks sooner than the normal Corn Belt harvest season that typically begins in late September and early October. As an agronomist working for Climate LLC, I conduct field-scale research in New Berlin, Ill. on one of the Climate Research Farms – part of a five-farm network that spans 6,000 acres – to grow our understanding of crop and soil trends and conditions.

The conditions I am experiencing in my area are reflective of what is happening throughout much of the Midwest. As you prepare for early harvest, here are some reasons why harvest is coming sooner this year and what you can do to protect yield and ensure everything goes as smoothly as possible.

Three Key Factors Related To An Early Midwest Harvest

1. High Corn Heat Unit Levels
In our area in Illinois, it has been an atypical year for charting corn growth and development. The cold, wet weather across the Midwest delayed planting for many, but most central Illinois farmers began putting seeds in the ground in late April and finished no later than mid May. The frigid early season temperatures were soon followed by higher-than-average temps and dryer-than normal conditions across most of the Corn Belt creating an excellent start to the growing season and resulting in fast emergence.

You’re probably familiar with corn heat units (CHUs) or growing degree units (GDUs) that measure cumulative heat over the growing season. Simply put, corn tends to grow faster in hotter weather and growth typically slows when it is cooler. Midwestern temperatures in the high 80s and 90s in May, June and early July, and the accompanying higher GDUs accelerated corn growth across much of the Midwest, and resulted in substantial corn dry down in some parts, which is now prompting an early harvest for many. In fact, it was the hottest May on record in Illinois** and in our area, we are seeing 2,963 GDUs compared to an 11-year average of 2,478 GDUs – approximately a 20% difference!

Higher-than-average GDUs were recorded across the Midwest between mid April and August helping to accelerate corn growth and maturity. The numbers indicated on this map indicate the difference between this year’s (higher) cumulative GDUs and the average cumulative GDUs over the past 66 years.***


Climate FieldView™ allows you to track the progress of crop development with GDUs for corn, cotton, sugar beets and soybeans.

2. Soil Moisture Variances
While much of central Illinois experienced hot and dry temperatures during May and early June, this was followed by near flood conditions in some areas and timely rains in late June and July, further promoting corn growth. Farmers usually love to see this balance of heat and moisture that provides their corn crops with solid opportunities for growth and development.

In our area, we’ve had over seven inches of rain over the past three weeks – two times what is typically normal. However, dry conditions have returned for much of the Midwest which can further contribute to dry down, and many farmers are noticing advanced corn crop maturity that appears ready for harvest. It is important to watch for signs like these and even subtle cues that your corn crops may be ready for an early harvest.

3. Early Corn Maturity
In these parts, many farmers are seeing the development of the black layer at the end of the kernel that indicates corn maturity and a harvest-ready crop. In fact, some Midwestern farmers are already experiencing corn dry down levels in their fields at about the same rate that typically occurs in early October. Indications are that corn crops are ready for harvest across most of the Midwest – and nation.

Black layer near the kernels indicating that this corn is reaching full maturity.

Is It Go Time?
What can you do to make sure your corn is harvested at the right time?

  • Don’t take anything for granted, especially the time of year. Although this may be earlier than you have harvested in the past, the rules have changed across much of the Midwest. Corn is drying faster than normal because of current warmer temperatures and longer days that are atypical in late September and October.
  • Scout your fields and take a close look at your ears of corn. If there is clear evidence of black layer corn and dry down, do a quick pinch test and check for root rot or disease – another sign that harvest is coming faster than you may think.
  • Review our recent blog post, “Here Comes Harvest: Making Sure Your Data is Ready to Yield Insights”. Now would be a good time to take another look at the setup tips that will help you be sure your combines are ready to hit the fields and are connected to your Climate FieldView™ account so you can gather valuable harvest data.
  • Consult your agronomy partner if you want a second opinion or you have more questions.
  • If you have questions about gathering harvest data that will help you make important decisions next year, contact your Climate FieldView dealer or the Climate Support Team at (888) 924-7475, or visit for more information.

Best of luck with harvest – and beyond!
** National Centers for Environmental Information, June 4, 2018.
*** Map used by permission of Iowa Environmental Mesonet of Iowa State University.

About The Author
Luke Cole grew up on a diversified multi generational family farm in central Illinois. He holds a Master of Science in Crop Science from the University of Illinois. Luke's work experience is in precision farming and agronomy.