After weeks of dry weather through August and into September, most of Iowa received some much needed, widespread rainfall last week. USDA’s latest weekly crop conditions and weather report shows statewide average rainfall for the seven-day period ending Sept. 13 was 3.12 inches, almost four times the normal of eight-tenths of an inch. Some areas of the state, in eastern Iowa, received as much as 6 inches during the week of Sept. 7-13.

“We finally got the rain, but it was a little too late,” says Mitch Sievers, farming in Buena Vista County in northwest Iowa.

Many soybean fields are ready to be harvested in his neighborhood, as the hot, dry weather in previous weeks speeded up crop maturity. Grain moisture in many bean fields has declined to 9% to 10%. Corn also dried down fast in the hot, windy days around Labor Day and the weeks before.

Sievers predicts combines will be starting to harvest full-bore soon in his area. The weekly statewide USDA survey shows as of Sept. 13 Iowa’s corn crop is 1% harvested. It also shows 1% of the state’s soybean crop is already harvested. “We expect to see improvement in the drought monitor this week as fieldwork and harvest ramps up across the state,” says Iowa Secretary of Agriculture Mike Naig.

The complete weekly Iowa Crop Progress & Condition report is available on USDA’s site at nass.usda.gov/ia.

Crop report

Most of Iowa had multiple days of much needed rain, which only left just 1.4 days suitable for fieldwork during the week ending Sept. 13, according to USDA’s National Ag Statistics Service. Field activities included harvesting corn for silage, moving old-crop grain stocks, and preparing equipment and bins for harvest.

Topsoil moisture is rated 12% very short, 21% short, 59% adequate and 8% surplus. Subsoil moisture is rated 20% very short, 31% short, 46% adequate and 3% surplus.

Corn is 90% in or beyond dent stage, over two weeks ahead of the previous year and five days ahead of the five-year average. Iowa’s 2020 corn crop has now reached 45% maturity, almost three weeks ahead of last year and one week ahead of average. Corn harvest for grain has begun across much of Iowa with 1% of the crop harvested. Corn condition is rated 42% good-to-excellent, a drop of 1% from the previous week.

Soybeans statewide reaching coloring or beyond have advanced to 79%. That’s over two weeks ahead of last year and one week ahead of average. Soybeans dropping leaves reached 41% as of Sept. 13, which is two weeks ahead of last year and six days ahead of average. Soybean harvest began in some areas with 1% of the crop harvested statewide. Soybean condition is rated 48% good-to-excellent.

Alfalfa hay third cutting is 96% complete, over a month ahead of last year and 18 days ahead of the five-year average. Pasture condition improved 5%, although it’s still just 17% good-to-excellent. Pastures are greening up as a result of receiving the much-needed rain. Cattle producers are continuing with supplemental feeding of hay.

Weather summary

A shift in the storm track brought the wettest week of the 2020 crop reporting season to Iowa. “Last week, more rain fell across the state than in the entire month of August, with a vast majority of reporting stations observing positive departures.

Eastern Iowa reported up to 5 inches of above normal rainfall,” says Justin Glisan, state climatologist at the Iowa Department of Agriculture. “Unseasonably cool conditions also blanketed the state due to extended rainfall and cloud cover. Temperatures were up to 14 degrees cooler than normal, with the statewide average temperature at 55.4 degrees, 11.3 degrees below normal.”

Weekly rain totals ranged from 0.41 inch in Rock Rapids (Lyon County) to 6.88 inches at DeWitt 4 (Scott County). Statewide weekly average precipitation was 3.12 inches, almost four times the normal of 0.84 inch.

Little Sioux (Harrison County) reported the week’s high temperature of 97 degrees F on Sept. 6, which is 18 degrees above normal. Holstein (Ida County) reported the week’s low temperature of 39 degrees on Sept. 9, which is 12 degrees below normal.

U.S. corn 5% harvested

Looking at the national scene, USDA’s Sept. 14 weekly crop conditions report shows U.S. corn and soybean crops are staying in a declining mode, similar to August. USDA now gives the U.S. corn crop a 60% good-to-excellent rating, versus 61% a week ago. The Iowa corn crop as of Sept. 13 has a good-to-excellent rating of 42%, a 1-point drop from a week ago. This contrasts to Minnesota’s corn crop, which is rated at 76% good-to-excellent.

USDA says 5% of the U.S. corn crop has already been harvested, and the five-year average is 5% for this date. USDA rates 89% of the nation’s corn now in the dent stage, versus a five-year average of 82%. They peg U.S. corn as 41% mature, which is ahead of the 32% five-year average.

USDA says 37% of the U.S. soybean crop is dropping leaves, versus a 31% five-year average. The soybean crop has a 63% good-to-excellent rating, versus 65% a week ago.