Late spring postpones
fieldwork, should we worry?
Tuesday, April 16, 2013 5:58 AM
"I can see no reason not to expect another good crop here in southeastern Minnesota," Jerrold Tesmer said last week.
Tesmer serves as an Extension Educator for the University of Minnesota's outreach program, serving Fillmore and Houston counties.
Even though a late spring is keeping farmers out of the fields, some good rainfall totals were piling up as frost finally left the ground. The month of March was consistently colder than normal with relatively heavy snow cover carrying over into April.
However, that blanket of snow may not have left much moisture in the subsoil, Tesmer noted.
"In this area, we had a concrete frost," he said. The term refers to a condition where most of the pore space in the surface layer of the soil is occupied by frozen water.
According to agronomists, concrete frost inhibits the soil's ability to infiltrate additional water. That means that most of the moisture locked up in snowpack takes a shortcut directly into streams and rivers when it melts, denying much needed water to the subsoil below the icy layer.
Formed when winter rains pool and freeze near the surface, concrete frost also takes a longer period of time to melt away than frost that forms during unsaturated conditions.
Fortunately, a rainy week seems to have showed up just as frost layers melted away, Tesmer said.
Near Harmony in Fillmore County, some farmers totaled over four inches of rain on April 9th through 10th. Spring Grove totaled 2.76 inches during a 48-hour period ending at 7 a.m. last Wednesday.
Over two inches of rain occurred at La Crosse, Wis., with more cold precipitation due for several more days.
When asked how much of the 4-inch bonanza soaked in, Tesmer replied, "That's the $10 million question... I don't know the answer."
"This cold wet weather is not that much fun to live through, but it's good for the ground."
"Last fall, we were scraping the bottom of the barrel as far as moisture. We needed a week to 10 days of cold wet rain to really soak in the soil. We haven't really got a lot of that."
Tesmer said that even though the last two winters were very different, they share some things in common.
"With carryover for the types of insects that burrow into the ground and overwinter here, we really haven't had a winter that hammers them in many years.
"What we'd really need is an open winter with really cold temperatures for a long period of time. We haven't had that. For those types of insects, a stretch of 20-below for seven days straight would kill a lot of the insect larva in the ground."
A late start to field work may be inevitable, but it's not time to panic yet.
"I know everybody would love to be in the field, but I'm fairly optimistic. There's no reason that if we get our rain and then get a week or two of nice weather, that things won't turn around real fast.
"The problem right now is that the guys who have beef cattle that are calving have got mud. It's not a good situation for them.
"We got 171 bushels per acre on corn in Houston and Fillmore counties last year. I can see no reason not to expect a yield like that again this year with current conditions. We've got moisture now. There's an old saying that 'Rain makes grain.'
"Obviously, I think we're probably a couple of weeks away before a lot of fieldwork gets done, but there's no reason that we need to plant corn as early as we did last year.
"Usually, when we get to the middle of May, that's when you're going to start losing yields on corn."
Lastly, the eastern half of Fillmore County and most of Houston County could have a bit of an edge when it comes to getting into the field during a rainy spring.
"We do have nice silt-loam soils here in southeastern Minnesota that dries fairly quickly," Tesmer reported.
"One year, we had corn a foot tall in eastern Fillmore and Houston County, and they hadn't even planted any corn in the western part of Fillmore County.
"We were getting rain about every third day. In Houston County, it was taking about 24 hours to dry enough to get back in the field, whereas the flatter ground with a little bit different type of soil took two days to dry. Every time that it would dry up enough for those guys to plant it would rain."