Jeff Graybill, a Penn State Extension agronomy educator, likes to “practice what he preaches” to other farmers by growing crops on his own 35-acre farm just outside of Manheim, Pa.

But he’s learned a valuable lesson this year about staying still in the spring. The evidence was clear when he recently dug up a few of his corn plants.

"I think guys don't dig roots. There’s probably 10% or 15% of the fields in this area have some of this this year because a lot of guys did the same thing. But if they don't go dig roots they don't really know," he says.

What did he find? Stunted roots, or what he describes as “paint brush” roots. Coupled with the fact that the seed trench was still wide open from this spring, Graybill’s fields have signs of sidewall compaction.

It’s a problem lots of growers see every year, but it’s something that can be avoided through a few simple steps. For Graybill, his mistakes were about timing and planting.

He does continuous no-till corn and soybeans with a three-way cover crop mix of triticale, ryegrass and crimson clover. He likes to plant corn or soybeans early in order to harvest by late September to get his cover crops in the ground.

“A week in September is like two to three weeks in October or November in terms of getting [cover crops] established,” he says.

This spring was cold and wet in Lancaster County, and in much of the region. Graybill terminated his cover crop mix around April 24. Since his job as an Extension educator has him away from the farm for much of the time, he uses a custom planter to plant his crops.

Like most other farmers, he got his corn and soybeans in later than he wanted this year. His DeKalb hybrid corn was planted two weeks after the cover crops were terminated. His shale soils were still wet, but since they usually drain well Graybill didn’t think anything of it. He wanted to get the crop planted.

Then it got hot and dry for weeks. The seed trenches were left open, allowing the sidewalls to smear and compact.

Looking at the stand you can see that it’s growing, but it’s uneven. Bugs and slugs have had a feast chewing on the roots. Even though his target plant population was 30,000, he estimates that between 21,000 and 22,000 plants are growing.

“When you think about the area of those roots to explore, you are limiting it and it can definitely increase the stress on the plant,” he says.

A nice soaking rain after planting would have probably moistened up the soil enough that it may not have compacted the way it did, but the mistakes, he says, were made at planting. He planted when it was too wet and the furrow was left open.

Graybill says that he should have waited a few more days to plant, but what if another rainstorm came through, pushing planting back to late May? It’s a problem with no easy solution.

How will it affect yields this year? Hard to say. Again, the plants look green, and a young ear that he pulled back looks nice, but it’s still early and time will tell what the rest of the season will bring.

Still, he’s already thinking about changes for next year. He may consider asking his custom planter to use spaded or spiked wheels instead of the standard rubber wheels to ensure the furrow closes properly. Perhaps the planter could’ve cranked down the down pressure, but the challenge with that is if you crank it down too much you pack the soil even more.

“You can hurt yourself, even in a system that's now fairly robust. I should have just waited, but it's definitely something to look for. You live and learn I guess,” he says.

Preventing sidewall compaction

Here are some tips from the Michigan State University Extension website — originating from Paul Jasa, agricultural engineer at University of Nebraska — on how to prevent sidewall compaction in corn and soybeans: