Note: You can listen to my conversation with Dan Gillespie by clicking on the Soundcloud link above.
This year was a tough one for cover crop growth. A cold fall and spring limited growth for those who planted covers like cereal rye last fall, leaving thin stands this spring and fields more exposed to winter annual weeds like henbit and pennycress — although cold temperatures also hindered weed growth.
"I have not seen, in my cover cropping career, a fall and spring back to back that have been this difficult for cover crops to establish and grow," says Dan Gillespie.
Gillespie, a no-till specialist and soil conservation technician with the Natural Resources Conservation Service, has planted cover crops like cereal rye on his own farm near Battle Creek, Neb., since the early 2000s. This includes planting annual waterways and, more recently, planting green — or planting soybeans into a standing cereal rye cover crop. In the latest Down in the Weeds podcast, Gillespie discusses some of the opportunities and challenges with these cover crop practices.
One of the most important, especially when it comes to planting green, is termination date.
"Termination date is key, because it's all about the moisture management in your soil profile. And right now, in our area we're a couple inches below normal precip for the year. We're planting green, and I'm kind of rolling the dice a little bit that I'm going to get some of that spring moisture, because the cash crop is planted, and it needs that soil moisture to germinate and grow," Gillespie says. "That's one of the gambles that some of the guys that have been with it a few years will take. I would suggest that if you're just starting out, and this is your first year, that you be pretty conservative and terminate that cover crop at 6 inches if you have to. You don't want to get burned your first year; that's a great way to lose your interest."
In the 2000s, Gillespie began planted cereal rye in flow areas to augment corn residue for erosion control. As discussed in an earlier Nebraska Farmer article, in 2008, Gillespie had an eye-opener in a soybean field planted where an annual waterway had been.
"I noticed the flow area I had planted the cover crop in at that point in time, it was a darker green hue, just the area I had planted that annual waterway in, than the rest of the field. It struck me immediately as there's something going on here, and it's something good," he says. "That's what led me to say, 'Let's plant the whole field.'"
"I hope maybe after trying the annual waterway thing, [other growers] see the benefit of that cover crop and expand it to the whole field, because then it becomes less about soil erosion and more about soil health and organic matter and weed suppression," Gillespie adds. "Annual waterways can control the ephemeral gully erosion, but if it's only in the flow area, you're not getting that benefit over your whole field."