October 31, 2014

Soil moisture levels need a boost before the soil freezes

Harvest is nearing completion, especially for northwest Iowa farmers, but Iowa State University Extension crop specialist Joel DeJong says the ongoing dry conditions are still raising some concerns. DeJong says the window of opportunity to recharge our soil moisture levels before the ground freezes is closing.

He says it’s very apparent that the drought has not ended. “We really still are not getting any significant precipitation, and normally this time of year you don’t get to harvest seven, 14, 21 days in a row, and we’ve had the opportunity if not more, because it doesn’t rain,” DeJong says.

The crops that are being harvested now had to work hard to get to the water that is there. “We did a field day this summer at Dordt College in Sioux Center and we dug some root pits to see how deep the roots went,” DeJong says.

“And we found roots at eight, eight-and-a-half feet deep. Well a foot of soil hold about two inches of water. I think in this part of the world we utilized a lot of whatever our rooting depth was, and right now that zone is pretty dry.” Based on the root tests, there needs to be quite a bit of precipitation.

“Really to catch up to get us at what we call field capacity, which is where we like to be by the middle of June when we really start using water, it’s going to take 14 to 16 inches of water to really get that recharge,” DeJong explains.

And the sooner the better, because once the ground freezes, the water will run off and not soak into the ground.

By Dennis Morrice, KLEM, Le Mars