As of May 21, Iowa farmers have planted 92% of the state's 2017 corn crop, which is three days behind last year's rate. The lag is mostly due to wet fields from recent storms. However, this spring’s corn planting progress is running two days ahead of the five-year average. Soybean planting is now 62% complete, two days behind last year, but only one day behind average, according to USDA’s weekly survey.

Farmers took full advantage of the less than 2.5 days suitable for fieldwork last week to plant 7% of this year’s anticipated corn acres and 22% of soybean acres. The spotty showers and sometimes heavy rains made it difficult to make much planting progress, especially in the later part of the week. “As we approach the end of May, farmers are very anxious to finish planting, and we hope for agreeable conditions to allow that to happen,” says Iowa Secretary of Agriculture Bill Northey.

The complete weekly crop and weather report is available at the Iowa Department of Agriculture and Land Stewardship or at USDA. The report summary follows.

Summary of weekly crop report
Statewide, Iowa farmers had only 2.3 days suitable for fieldwork during the week ending May 21, according to USDA’s National Agricultural Statistics Service. Those few days came early in the week, as rain throughout the rest of the week made conditions too wet for planters to enter the fields.

Topsoil moisture levels rated zero percent very short, zero percent short, 65% adequate and 35% surplus. Subsoil moisture levels rated zero percent very short, 1% short, 71% adequate and 28% surplus.

Corn condition is 63% good, 12% excellent
As of May 21, the survey shows 92% of the 2017 Iowa corn crop has been planted, three days behind last year, but two days ahead of the five-year average. Corn emerged reached 59%, four days behind last year. The first corn condition rating of the season was 1% very poor, 2% poor, 22% fair, 63% good and 12% excellent.

Soybean planting in Iowa reached 62% complete, two days behind last year, but one day ahead of average. Also as of May 21 in Iowa, 15% of the bean acres have emerged, one day behind average. Oat emergence reached 92%, two days ahead of average. Oat condition is rated 80% good to excellent.

The first cutting of alfalfa hay advanced to 8% complete. Hay conditions decreased slightly to 82% good to excellent. Pasture condition remained at 82% good to excellent. The week’s rain resulted in muddy feedlots again, stressing some cattle.

Weather summary for Iowa
The weather reporting week began with dry and very warm weather on May 14, with afternoon highs in the 80s statewide. However, the remainder of the week brought frequent rain and several episodes of severe weather.

“On Monday, May 15, and later that night, we had thunderstorms in the northern one-third of the state,” notes Harry Hillaker, state climatologist for IDALS. “Rainfall amounts with these storms were mostly under one-half inch. However, severe weather in the form of hail and high winds was reported from 20 counties Monday evening into early Tuesday morning.”

High winds and large hail in 24 counties
May 15 was very warm and humid, with temperatures reaching 94 degrees at Shenandoah, he reports. Temperatures again climbed into the 80s statewide on May 16, with thunderstorms erupting over about the northwest one-half of Iowa on Tuesday evening and night. Rainfall amounts of 1 to 2 inches were common with these May 16 storms, with high winds and large hail reported from 24 counties centered from west-central across to north-central Iowa.

May 17 was the most active weather day of the week, with thunderstorms statewide. Severe weather, mostly high winds, were reported from 55 counties Wednesday evening, May 17, mostly across the eastern two-thirds of the state. Much cooler weather prevailed for the second half of the week. May 18 was dry during daylight hours, with high temperatures in the mid-50s northwest to mid-70s southeast. However, showers and thunderstorms brought statewide rain on the night of May 18 through Saturday May 20. Daytime highs were only in the 40s and 50s May 19. May 21 was mostly dry, with highs in the upper 40s northeast to mid-60s southwest.

Statewide average rainfall 2.5 times normal
Weekly rain totals varied from 0.76 inch near New London in Henry County to 5.78 inches near Mondamin in Harrison County. The statewide average precipitation was 2.56 inches or nearly 2.5 times the weekly normal of 1.05 inches. This was the highest weekly average in the state since the third week of August in 2015.

Very warm weather early in the week was basically canceled out with much colder weather during the second half of the week, with a statewide average temperature of 0.2 degree above normal. The week’s lowest temperatures were 36-degree readings at Sibley, Sioux Center and Sheldon on the morning of May 21.