What’s Up in Crop Production So Far
What’s Up in Crop Production So Far
Editors come across some pretty interesting things when we travel across farm country each growing season. Here are some odds and ends that I’ve picked up so far.
Onion in the Petunia Patch
There’s a saying about an “onion in a petunia patch.” This means an oddball, out-of-place thing in an otherwise seamless tapestry of uniformity. I’d have to rank this cattail in this corn field (mine, actually) as the onion.
Cattails are popping up in crop fields in water-saturated areas like northeastern South Dakota. Fortunately, they’re mainly a minor annoyance.
If you’re being taken over by them, though, there are control methods. When Chris Boerboom was Extension weed specialist at the University of Wisconsin, he developed some guidelines to control cattails in corn. Tillage is a first option. Then, although rate and timing may be challenging to include in standard application programs, he found glyphosate may be the best way to control it, particularly in no-till corn.
Don’t Forget the Surfactant
University of Missouri Extension agronomy specialists note some glyphosate labels have rates as high as 3 quarts per acre at flowering for control. Including a surfactant is recommended, as droplets may roll off the leaf surface.
In corn, Boerboom found dicamba-based herbicides like Banvel, Clarity, and Status can suppress cattail when tankmixed with glyphosate.
Wheat Stem Sawfly
Wheat stem sawfly is a serious wheat pest in western and northern states, says Ada Szczepaniec, South Dakota State University Extension entomologist (blue shirt). Larvae overwinter in stalks of grasses like wheat, with adults emerging in late May or early June. Eggs laid early in the growing season hatch later inside wheat stems. The emerging larvae damage wheat plants by internal feeding.
There’s good news, though. Wheat stem sawfly can be foiled by trap cropping oats on borders of wheat field. Although the insect is attracted to oats, it can’t survive in that crop.
Stack the Deck
“Stacked rotations” are those where crops or crops within the same crop type are grown in succession – normally twice – followed by a long break, says Dwayne Beck, manager of the Dakota Lakes Research Farm, Pierre, South Dakota (white striped shirt).
Wheat-wheat-corn-corn-soybean-soybean is one example. This throws off pests by keeping crop sequence and crop interval diverse.
How Stacks Started
Ever wonder where that came from? Back in the early 90s when the farm program had base acres, South Dakota farmers wanted to maintain their 50% base of wheat acres. “So, we came up with a wheat-wheat-corn-broadleaf rotation that preserved 50% of their wheat base,” says Beck. This also sparked rotational diversity.
Decades, Not Years
Ever read articles about raising organic matter levels by 1% in a couple years after adopting cover crops and no-till? It’s not that easy, says Jason Miller, a Natural Resources Conservation Service agronomist. Sure, these tools play a role in doing so. But raising organic levels this much is measured in a decades, not years.
It’s Worth the Wait
Once you do this, though, you’ll reap the benefits. The long-term value of a 1% organic matter increase is estimated at $24 per acre in nutrient value and available water holding capacity, says Miller. (These estimates are based on an average 17 inches of precipitation in central South Dakota, and can vary between locations.)
Cattails in corn, wheat stem sawfly, how stacks started, raising organic matter takes time.