Recent rains have brought an official end to drought conditions in eastern Iowa, but southwest Iowa’s drought recovery hasn’t been quite as swift.
The USDA drought monitor shows nearly 20 percent of Iowa, all on the eastern side, is now out of drought conditions. That’s up from less than 7 percent of the state just two weeks ago.
Approximately 20 percent of the state, mostly in northwest Iowa, remains in extreme drought conditions. Still, that is considerably better than last September, when 65 percent of the state was considered to be in an extreme drought.
Last week, Iowa experienced its wettest week since July 2010 with a statewide average of 2.90 inches of rain, compared to a weekly normal amount of 0.78 inches.
And, with cool and damp weather in the forecast for today through the end of the week, further recovery of subsoil moisture and farm ponds should continue in south-central Iowa. Now, the emerging concern could be the delay in getting in the fields to plant the 2013 crop.
“We still need rain anytime we can get it,” said Tracy Cameron, agronomist for Gavilon Ag Service, “but pretty soon you’ll hear griping about getting into the field. From now on is a good time to plant corn. As soon as it dries up, it’s time to plant corn.”
Above-average snow cover and a chilly, wet spring have helped restore moisture to many states stricken by last year’s drought. In much of the farm belt, there’s enough topsoil moisture to allow plants to emerge.
“With the rains and cool weather, it’s been too wet and the soil isn’t ideally warm enough to get in the field and plant,” said Harry Hillaker, state climatologist. “Creston has not been as wet as eastern parts of Iowa, but we’ve seen improvement in the drought status.”
Currently, Union County is in the “moderate” drought category, which is the second-least severe in a five-point scale.
“Last week northwest Iowa was the only area still in the extreme drought situation,” Hillaker said.
A contributing factor was lingering frost in the ground in the northwest sector, where several inches of snow and ice accompanied the past week’s weather pattern that brought a nice, soaking rain to thawed ground in Union County and surrounding areas.
Rainfall in Creston in March was 1.30 inches, Hillaker said, followed by 1.5 inches to date in April, including more than an inch in a slow, soaking rain Wednesday and Thursday last week. Much of the same was expected today and Thursday.
Year-to-date, Creston’s precipitation is 6.31 inches, which is above “normal” of 5.64 inches.
“The significance of these last rain events is that it occurred on thawed-out ground, so it can really soak in,” Hillaker said. “There was some winter snowfall on frozen ground that was runoff, which helped fill farm ponds and streams that were depleted from last year. From February to now, we had above-average snowfall. In some parts of south-central and southwest Iowa, you can add two to three inches of rain on top of that.”
The component still in question is deep moisture, which fed last year’s crop during the extended dry spell. In those conditions, last year’s crop depleted subsoil moisture.
The National Drought Mitigation Center at the University of Nebraska released Thursday said the weather has likely recharged the top two inches of soil, which supports planting and early emergence. But, continued substantial rainfall will be needed to improve subsoil conditions.
On this week’s USDA crops and weather report, subsoil moisture levels rated 27 percent very short, 42 percent short, 29 percent adequate and 2 percent surplus.
“This rain we got recently will help the topsoil part,” said Wayde Ross, Natural Resources Conservation Service district conservationist for Union and Ringgold counties. “But our (soil conservation) contractors say it’s dry down as deep as they can dig. It will still take timely rains to keep things going. The subsoil needs replenished.”
And, not everyone received slow, soaking rains during recent weather events.
“Around Beaconsfield and Kellerton, they got hammered with that first good rain with about three inches in 45 minutes or less,” Ross said. “There was a lot of erosion.”
With highs in the 40s and lows in the 30s for several days recently, soil temperatures have also cooled below sufficient planting conditions.
“When we had that niche of 77-degree days, we were there where we wanted with soil temperature as high as 57,” Cameron said. “But last week it got back down to 44 degrees. You like to have 50 and above, along with a good forecast so it doesn’t dip down again.”
Keeping farmers on edge this year will be the knowledge that subsoil moisture isn’t the “reserve tank” they had last year to bail out a thirsty crop. And, Hillaker said history shows the year after a severe drought often brings a similar warm, dry summer. Just not as extreme.
This year’s crop will only be successful if there is normal rainfall through the growing season.
“When you look back to the drought of 1988, we received timely rains in 1989,” Cameron said. “We raised a crop because of that, even though was no water in the soil. It’s hard to count on that, but I think we’re better off than some think in our subsoil. We are not full, but I’ve seen moisture accumulate since October.
“I think we’re a rain away from seeing some tile lines starting to run,” Cameron added. “Some growers have already seen that. That’s a sign we’re getting recharged.”