Wheat Needs Sustained Mild Weather
Winter wheat growers should hope for two more weeks of mild weather to avoid the kind of soil-heaving problems that seriously damaged last year's crop, says an Ohio State plant pathologist.
Abrupt temperature fluctuations above and below freezing can cause soils to expand and contract, which push plants up and out of the soil, says Pat Lipps. Last year's wheat suffered from considerable soil heaving, followed by serious disease problems that caused significant yield losses.
The crop will be at risk if temperatures dip down to 20 degrees F at night and rise to the 40-degree range during the day, Lipps says.
"If the temperatures stay steady in the low-30 to mid 30-degree range until March 15, it shouldn't hurt the wheat," he says.
Lipps says wheat has broken dormancy two weeks early, which could also expose it to late winter damage if temperatures suddenly plunge without significant snow cover. The threat of winter damage usually lasts through mid-March.
"The wheat is starting to green up earlier than what I'd like," Lipps says. "I'd like to see it dormant another two weeks to get it past the time when there's any real danger from cold temperatures."
Recent wet weather probably won't hurt the crop or cause any premature disease problems, Lipps says. Soil heaving is the most serious thing that could happen at this stage of the season.
"After this time of year, the plants can maintain a lot of moisture and even remain underwater without much of a problem," he says.
Now that plants have begun to green up, it is a good time for farmers to see if their wheat needs an early-season nitrogen application, Lipps says. Fields need fertilizer if they have fewer than 18 to 22 plants per row-foot. Count only those plants with two to three leaves, he says.
Normally farmers apply nitrogen from March 15 through April 15. However, the wheat could use an earlier boost if it didn't get sufficient growth due to late-fall planting. Most farmers planted their wheat at least seven to 10 days late because they were busy harvesting a late soybean crop.
"People could go out and evaluate their stands now," Lipps says.