Wheat was a superstar for growers in the Upper Southeast this year, with above- average yields and test weights common across the region.

Acreage is expected to increase again as growers get ready to plant the 2012 crop this fall. To continue the upward trend in yields, North Carolina State University Small Grains Specialist Randy Weisz and USDA-ARS Plant Pathologist Christina Cowger agree dialing in the right variety is essential.

Cowger and Weisz go a step beyond Official Variety Tests (OVT) results in recommending wheat varieties for the 2011-2012 crop.

“We use additional tests not available to the OVT, and we sometimes exclude low-yielding locations used in the OVT program,” Weisz says.

The North Carolina researchers also examine variety yield and stability of variety performance across multiple years and multiple regions of the state.

“Above average yielding varieties are always a good place to start, but yield is not the only factor to consider,” Weisz says. Yield should be weighed along with the following criteria, he contends.  

• Avoid spring freeze damage. Early heading varieties are the most susceptible to damage from late spring freezes. “To reduce risk of yield loss to late-season freezes, growers should plant no more than one early or mid-early maturing variety. To further hedge against freeze damage, growers should plant at least one late-heading variety,” Weisz says.

• Pick varieties that will hold up against the typical problems in a particular region. For example, says Cowger, in the Piedmont of North Carolina the most commonly occurring yield robbers are late spring freezes, barley yellow dwarf virus (BYDV), and Fusarium head blight (scab). In that region of the state, a high-yielding variety with late maturity and some resistance to scab and BYDV would be ideal. 

In the Tidewater Region of North Carolina, scab is also common, but Hessian fly and wheat soil borne mosaic virus are more likely to create problems than BYDV and spring freeze. 

For the Coastal Plains, an ideal variety would have resistance to powdery mildew, leaf rust, and soil borne mosaic virus. Variety selection should be fine-tuned to the region in question.

Though planting wheat varieties from three different heading date groups is a proven formula for successful yields and quality, some growers simply can’t follow the formula, because they want to plant extra early to beat soybean or cotton harvest.

This spring, heat and lack of soil moisture pushed back planting dates throughout the Upper Southeast. As a result harvest dates for corn and soybeans will be erratic and generally pushed back a week or two in the Carolinas and Virginia.

Some growers will likely take the opportunity of the lull between corn and soybean harvest to plant wheat.

For growers who are planting wheat 10-14 days earlier than recommended, dialing in the right varieties is even more critical to getting profitable results, Weisz says.

Have tested early-planting system

“We have tested a system in which growers can plant in late September or early October, usually 10-14 days ahead of recommended planting dates and still get good yields and quality,” he adds.

For growers planning to plant wheat much earlier than usual, the North Carolina State specialist says to follow three basic steps:

1.) Plant at a 2/3 normal seeding rate.

2.) Plant only seed treated with an insecticidal seed treatment like GauchoXT or Cruiser/Dividend.

3.) Plant by the last week in September in the Piedmont and by the first 10 days in October in the Tidewater Region.

Cowger, who works with USDA’s Agriculture Research Service at North Carolina State University, has tracked scab-related wheat yield losses for several years.

“Variety resistance is the best defense against scab,” she says. “A number of high-yielding varieties with good levels of scab resistance are now available to North Carolina growers. In addition, planting at least three varieties with different heading dates is a good hedge against yield loss,” she adds.

With different heading dates, all the wheat will not flower at the same time. Cowger stresses growers should also avoid planting late, because that means late flowering and more risk of scab problems in late spring, when temperatures and, often, more rainfall increase the risk of scab.

In 2011, Cowger says, there was very little scab anywhere in the region. Though not the only reason wheat performed well in the Upper Southeast this year, not losing yield to scab clearly contributed to high grain yields and uniformly good quality across the region.

Though not directly related to varietal selection, different varieties react differently to stress, including competition from weeds and grasses. It may be easier to plant wheat in the fall, forget about it until spring, and manage weeds at that time, but that scenario is unlikely to give any wheat variety its best chance to achieve high yield and good quality.

Letting management slip in the weeks after planting can be a yield robber, especially with the crop price stakes elevated this year.

Sometimes, when growers get row crop harvest going in the fall, they don’t think about weed control in wheat until the spring, and that’s often too late.

Unpredictable spring weather and weeds hardening off in the winter can mean a tougher time managing weeds in the spring. The main benefit of a fall herbicide application is decreased early weed competition, which can pay off in higher yields.

The best time to manage Italian ryegrass is in December. At the end of the season, less weed seed and dockage mean a premium price at the elevator.

Back to back high wheat yields will be a life-saver for some Upper Southeast growers, making up for below average corn and soybean yields, a result of prolonged heat and drought throughout much of the growing season the past two years.

To give wheat the optimum chance for achieving high yields and quality Weisz and Cowger urge growers to consider multiple performance factors before choosing a variety.

rroberson@farmpress.com