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July 16, 2019

U.S. Crops show Slight Improvement - High Temperatures Worry

Author: Michael Cordonnier/Soybean & Corn Advisor, Inc.

Corn - The weather last week was OK, but if we stay in this hotter and dryer pattern going forward, I am concerned that moisture stresses may increases. As I said last week, one week of warm and dry conditions was beneficial for the crops. Two weeks of those type of conditions was neutral and three weeks would start to be a negative. We are now at the start of week number three and the forecast is calling for more hot and dry conditions especially in the central and west-central Corn Belt.

The track of the moisture from Hurricane Barry could be very important for the areas of the Corn Belt that have recently experienced dryer conditions. The driest areas of the Corn Belt are Iowa, northern Missouri, and western Illinois and it remains to be seen if the moisture from Barry makes it way that far west.

The corn condition improved slightly last week and it is now rated 58% good to excellent compared to 72% last year. The warmer and dryer weather helped some areas and it hurt other areas. The corn silking is now 17% compared to 59% last year and 42% for the 5-year average. The silking is slow in the eastern Corn Belt where Illinois is 19% silked (average is 67%), Indiana is 10% (average is 44%), Ohio is 6% (average is 30%), and Michigan is 0% (average is 14%).

Silking is also slow in the western Corn Belt with Iowa 8% (average is 40%), Nebraska is 11% (average is 42%), South Dakota is 0% (average is 21%), North Dakota is 1% (average is 15%), and Minnesota is 2% (average is 23%).

The U.S. corn crop will reach 50% silked probably at the end of July. Pollinating at the end of July could be problematic, but it's not the "end of the world." I am much more concerned about the very late planted corn that may not pollinate until later in August.

Pollination is the most important time for the corn crop, but several weeks prior to pollination is also very important because that is when the size of the ear is determined. If the corn plant is under moisture stress prior to pollination, it sets a smaller than average ear, which cannot be changed going forward.

For the early planted corn, I think there is probably enough subsoil moisture to avoid any significant moisture stress prior to pollination. Once again, my major concern is for the later planted corn that will set the ears and pollinate during August. There are reports already of corn rolling their leaves in Illinois, Iowa, and Indiana. The high temperatures forecasted for later this week are going to stress the corn, especially in areas that remain dry. As the soil moisture declines, the later planted corn could run into moisture stress prior to and also during pollination.

Soybeans - The condition of the 2019 soybean crop improved 1% last week and the soybeans are now rated 54% good to excellent compared to 69% last year. The soybeans are 95% emerged compared to 100% last year and 99% for the five year average. The soybeans are 22% flowering compared to 62% last year and 49% for the 5-year average.

Hot and dry conditions during the second half of July and the month of August would certainly be bad news for the late planted soybeans that are slow in their development. Adverse weather would slow their development even more and guarantee shorter than normal plants with an increased probability of below average yields.

The path of the moisture from Hurricane Barry will be important, at least in the short term for the soybeans. I am most concerned about central and southern Iowa where the soil moisture is in the range of approximately 20-40% short to very short, northern Missouri, and western Illinois.