It’s 92 F. in central Iowa today. This test field of corn on sandy ground is holding up well — despite only 4.1 inches of rain between May 1 and last weekend, when the area received rains totaling an inch.
August 26, 2020 — The field trial, in cooperation with Adaptive Symbiotic Technologies, is one of several we’re watching this summer. Dry weather stress in central and western Iowa is offering a good challenge for the “endophyte” organisms developed by the firm to help crops withstand stress.
We’ve detailed the science behind this technology previously; check it out here.
Today, our research cooperator texted this photo of corn which was foliar-sprayed with BioEnsure on June 8. This field is on light sandy soil. Seasonal rainfall on official records: May, 2.4 in., June, 1.5 in., July 0.11 in., and so far through Aug. 26, 0.09 in. The grower reports one very localized shower last weekend which didn’t extend to the Fort Dodge, IA station of record.
The grower notes that finally, the corn is “running out of water.” There’s some firing below the ear, but leaves above the ear are still green. Ears are typically 20 rows around, with 36 kernels per row. Only a half-inch of tipback on most ears. The cooperator says kernel depth is good. The milk line has receded about a fourth of the way toward black layer toward completion of maturity, so there’s still some filling time as August winds down. A good rain would still help.
The field could finish up with that ideal look — white husks on still-green stalks.
As we’ve scouted fields here in northeast Iowa’s Grundy County, the corn Mecca of Iowa, most of the corn on sandy knolls is dead — and our local counties were the rain-blessed garden spot of Iowa this season until the rains almost disappeared in August.
Update September 7 — Here’s corn in the same field, which still has significant green above the ear. Kernels have reached black layer. This field is achieving the objective of mature ears with life left in the stalk, so moisture can move out of the kernels and cob back through the stalk’s vascular system. The field received .45 in. of rain September 5, which will help maintain life in the upper stalk.
Many surrounding cornfields have been totally brown for two weeks or more. In Pocahontas County and farther toward southwest Iowa, combines are starting to roll through corn.