Iowa’s 2018 corn crop is rated 75% good-to-excellent in the latest USDA survey, based on conditions as of Aug. 12. That’s the same rating as the previous week. Iowa’s soybean crop, however, has slipped to 72% good-to-excellent. It was 74% in that category the week before.

“We continue to see spotty showers across the state with some areas receiving strong storms and other areas, especially southern Iowa, are extremely dry,” says Mike Naig, Iowa ag secretary. Subsoil moisture is now 31% short or very short in the state. In south-central and southeast Iowa, “over 85% of the land is short or very short of moisture,” he notes.

Corn often looks good from road
The first six rows or so into the cornfield are average or better in terms of yield prospects, says central Iowa farmer Joe Samuelson. “But farther into the field, the crop condition falls off,” he adds. “We are seeing a lot of tip-back; ears aren’t filled out all the way to the tips. And kernels are smaller than normal, and now are all dented. Test weight is still to be determined, but I predict it will be below average in a number of fields here in Jasper County.”

Soybean plants look average or some fields are slightly below average in his fields, he says, but are still good. “Pods aren’t developing as well as they should, and more heat and dry weather for the next few weeks is in the forecast,” Samuelson says.

ISU drought meeting in southern Iowa
Iowa State University Extension will host a meeting Aug. 20 to discuss drought conditions that are causing concerns for both crop and livestock producers. The meeting will take place in Lucas County in south-central Iowa at 6:30 p.m. at the ISU McNay Research Farm, 45249 170th Ave. near Chariton.

The meeting will be hosted by ISU Extension specialists. Topics to be discussed during the meeting include crop growth and development under drought conditions, feeding drought damaged crops, silage and crop insurance considerations.

Crop report
Iowa farmers had 5.5 days suitable for fieldwork during the week ending Aug. 12, according to USDA’s National Ag Statistics Service. Activities for the week included harvesting hay and oats for grain, spraying for aphids, and moving grain.

22% of Iowa corn dented
Topsoil moisture rated 12% very short, 23% short, 62% adequate and 3% surplus. Subsoil moisture rated 10% very short, 21% short, 66% adequate and 3% surplus. Subsoil moisture in south-central and southeast Iowa remains critical with over 85% of that area rated short to very short.

The weekly survey shows 73% of Iowa’s corn crop has reached dough stage or beyond, nine days ahead of the five-year average. Corn dented as of Aug. 12 was at 22%, nine days ahead of last year. Corn condition rated 75% good-to-excellent.

Bean crop development ahead of last year
The survey showed 96% of 2018 Iowa soybean crop blooming last week, with 89% setting pods; that’s over a week ahead of both last year and the five-year average. Soybean condition declined slightly to 72% good-to-excellent. Iowa’s oat crop was 93% harvested for grain as of Aug. 12.

Third cutting of alfalfa hay was 47% complete in Iowa, four days behind the previous year but 4 days ahead of average. Dry conditions have kept alfalfa regrowth very short following the second cutting this summer. Hay condition fell to 56% good-to-excellent as of the end of last week. Pasture conditions declined to 44% rating good-to-excellent. Pasture regrowth is a concern, especially in southern two-thirds of Iowa.

Weather summary
According to Justin Glisan, IDALS climatologist, the first full week of August saw warmer conditions for much of Iowa, with average temperatures 1 to 3 degrees above normal in most places.

Rainfall accumulations were also above average across a swath of Iowa between Webster and Dubuque counties, with some locations reporting rainfall from 3 to 5 inches above normal. Aug. 6-7 had daytime highs well above average, especially in south-central Iowa, where highs reached the upper 90s. Lamoni (Decatur County) had the week’s high temperature of 100 degrees.

Heaviest rain in Webster, Buchanan counties
During last week, a low-pressure system moved slowly across Iowa, bringing measurable precipitation to much of the state, with the heaviest rainfall occurring in Webster and Buchanan Counties. Fort Dodge in Webster County recorded the week’s highest accumulation of 5.95 inches, 5.81 inches above average.

Multiple rounds of showers and thunderstorms continued into Aug. 7, with nearly 20 stations reporting rainfall above 1 inch; Guttenberg in Clayton County observed 2.36 inches of rain, 2.23 inches above normal.

Storms severe in Black Hawk county
A few thunderstorms became severe, with one report of 63-mph wind gusts in Black Hawk County. Aug. 8 was a pleasant day statewide, with average highs in the lower 80s. A weak cold front moved across Iowa on Aug. 9, firing off a few spotty thunderstorms in Iowa’s southeastern quadrant. Cedar Rapids in Linn County reported 0.07 inch of rain. Aug. 10-12 was warm and mostly precipitation free, as a high-pressure system moved into the Midwest.

A few thundershowers brought measurable rainfall to a handful of stations. Mount Pleasant reported 0.05 inch on Aug. 10. Over this three-day stretch, statewide average highs were in the upper 80s, with lower 90s in south-central Iowa.