Farm Journal experts are ready with solutions
You can find answers to your crop production questions on Farm Journal’s "Ask an Agronomist" blog. A team of Farm Journal agronomists and experts responds to questions sent to firstname.lastname@example.org based on their independent experience and in-the-field insight. Here are four questions and answers from the blog:
Q This year we had spots in the corn field that were black and dead early, with no ears on them. What would have caused these?
A There could have been multiple issues leading to no-ear stalks. One that we look for first is corn nematodes. They could have put enough stress on the plants, in conjunction with the drought, that the plants died early. You can confirm a problem with a soil sample. Evaluate corn nematodes in particular if you’re in a cornon-corn rotation.
Some of the problem could be related to soil type. What is your ground’s water-holding capacity? Some soils are able to hold more water than others. Did you notice whether you had any pockets of ground (from the size of a pickup to a house) that had barren stalks?
We saw this problem in three places and excavated the pockets of ground. There was a noticeable difference in the soil moisture at 18" to 20" deep in those pockets. When we got to a depth of 4' to 5' under the dead areas, we were finding bands of sand or gravel in the soil. Those bands of sand and gravel restrict water from moving up to where corn roots can access it, causing a perched water table.
In years with normal rainfall, the water table is high enough, but when it’s pulled below a certain level, as it was this year, the corn burns up. That was our preliminary finding this year.
Q Many of the farmers in North Dakota have forgone wheat plantings in their traditional rotation and are going to soybeans after soybeans for multiple years. What should they consider for soil health, disease prevention, etc., to maintain viable plants and yield?
A I would encourage farmers to entertain planting a cover crop such as rye. That will give them some diversity and complement soil health as far as soil structure and aggregate ability.
Q I didn’t have much of a corn crop this year, and the weeds turned some of my fields into a jungle. Would it be OK to moldboard plow those fields, just to get rid of the weeds?
A That’s a pretty radical option, but it might help bury weed seed that’s present so it doesn’t sprout and interfere with next year’s crop.
For plowing to be effective, you must understand each weed species that’s out there because some weed seeds need to be buried longer than others. I’d avoid plowing if you can, but if your weed seed bank is completely out of control, then that mightbe a good option.
- December 2012