If you want to know how dry the subsoil is, ask a grave digger.
“It’s dry as a bone once you get below 6 inches,” said Carl Thoresen, superintendent at Oak Hill Cemetery in Cedar Rapids.
Thomas Higgins of Independence, a grave digger for 28 years, said he’s finding moisture to 2 1/2 feet in rich black soil,
“After that, it’s hard as a rock, like concrete, the toughest digging I’ve ever seen,” Higgins said.
Thoresen said near-normal, late autumn rains have greened the grass and replenished topsoil moisture, but digging a grave, even with a backhoe, continues to take much longer than normal in the state’s driest year since 1988.
Despite welcome recent rains, Iowa’s statewide precipitation deficit for the year stands at 8.36 inches, according to State Climatologist Harry Hillaker.
That deficit has fallen slightly from 9.69 inches on Oct. 12 — the low-water point of the year, Hillaker said.
“Still, the deficit is the same as it was on Sept. 27, so we are not making great headway,” he said.
The spatial footprint of the drought of 2012 has changed little in recent months, but the intensity level has subsided, said Mark Svoboda, a climatologist at the National Drought Mitigation Center in Lincoln, Neb.
As of Nov. 13, more than two-thirds of the state remained in severe, extreme or exceptional drought, with the other 31.35 percent — including most of the eastern third of the state — experiencing moderate drought conditions, according to the Drought Monitor, published weekly by the Drought Mitigation Center.
The most recent monitor also shows the portion of the state in extreme or exceptional drought has shrunk from 75.3 percent during the first week of October to 41.7 percent.
While the drought has been “sort of lying dormant,” Svoboda said “this drought will be here next year.”
With little moisture in the subsoil bank, Midwest grain farmers “will be living rainfall to rainfall” starting early in the next growing season, he said.
Comes in pairs
Svoboda said he bases that assessment in part on the historical fact that droughts often come in pairs, as in 1988 and 1989 and in 1955 and ‘56, or in close sequence, as in 1934 and ‘36 and 1974 and ‘76.
In the annals of dry years, 1988 was the third driest; 1989, the seventh driest; 1955, the fourth driest; and 1956, the sixth driest, according to Hillaker.
“Farmers are talking about that” trend toward paired drought years, said Dave Miller, Iowa Farm Bureau Federation director of research and commodity services.
Miller, who farms in Lucas County south of Des Moines, said farmers “are going to be on pins and needles next year” unless subsoil moisture is recharged.
“We can grow a crop without a recharge, but it would take perfectly timed growing season rains, and the chance of that happening is next to zero,” he said.
Grave digger Higgins’ assessment is confirmed by the latest soil moisture statistics, which show improvement in the topsoil but not in the subsoil.
Topsoil moisture is rated at 59 percent short or very short, while 92 percent of the state’s subsoil falls into those two categories.
In fact, topsoil moisture is actually better than it was a year ago, when 63 percent was rated short or very short.
Such is not the case at the subsoil level — the bank from which next year’s crops will make withdrawals — where 92 percent is rated short or very short, which compares with 71 percent of the state’s subsoil in those two categories a year ago.
Hillaker said the state appears to be headed toward its ninth driest year in 140 years. As of Nov. 15, statewide precipitation averaged 24.72 inches, which compares with the normal average of 33.08 inches for the first 10 1/2 months of the year.
Above-normal rainfall in October has improved stream flow in Iowa, according to Tim Hall, coordinator of the Governor’s Drought Task Force.
Earlier this year, “the U.S. Geological Survey had to modify some of its gauges” in order to get accurate flow readings, Hall said.
Hall said Department of Natural Resources fisheries biologists remain worried that winter fish kills will occur, especially in shallow lakes with little inflow.
“The reality is, we don’t get a lot of moisture over the winter months. Precipitation during the March through June period will be critical for next year’s growing season,” he said.