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When Are Corn And Soybeans Ready For Harvest?

Soybean planting date is especially apparent now that harvest is quickly approaching. The Clinton Agronomy in Action site soybeans pictured above on the left were planted at the end of May, while the ones on right went in the ground at the end of April. 

There are a few things you’ll want to check off your to-do list before the combines start rolling through fields. Getting your combine ready to start picking corn and soybeans is probably one of them, but you also want to make sure you know which fields to start harvesting first. Here are a few management techniques to help you prioritize.

Assess Corn Stalk Strength
Even if your hybrids are standing tall and straight right now, a big wind storm could change all that and lead to reduced harvestability. There are a few factors that will determine how the stalks will hold, including:
  • Fungicide applications: If you have fields that didn’t receive a fungicide application, they should be harvested first. When corn plants aren’t protected with a fungicide, diseases rob plants of key nutrients that promote stronger stalks and healthier roots, which means a more difficult harvest.  
  • Lower nitrogen levels: Since some Illinois cornfields have been deluged with rain this season, many crops have experienced lower nitrogen levels. When there’s less nitrogen, there’s often higher levels of disease. Greater prevalence of disease often leads to weaker stalks and roots, therefore making it easier for your hybrids to topple. 
To help determine which of your cornfields you should start combining first, try the pinch or push test on each one. Pinch stalks toward the bottom, below the lowest node, to check for firmness. For the second standability test, push the corn plant 30° at waist height to see if it returns to an upright position with the stalk intact. With either test, there is significant lodging potential if 10 to 15% of the plants fail either test. The fields that pinch or push easily should be harvested first.

Calculate Soybean Moisture
When it comes to combining soybeans, planting date and moisture levels are the 2 key factors for determining which fields should go first. Most farmers plant varieties ranging in maturity to space out harvest dates. A relative maturity variance of 2.7 to 3.7 is a good range for many Illinois soybean fields. The other factor is moisture levels. Overnight dew can raise moisture by a couple points, while windy and hot, dry weather can quickly lower moisture levels. The ideal level is between 13% and 15%

We wish you a safe and successful harvest, and if you’d like to learn more and/or visit the Clinton Agronomy in Action site, contact your Golden Harvest Seed Advisor.

Photos are either the property of Syngenta or used under agreement.

Syngenta hereby disclaims liability for third-party websites.

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