Winter wheat seeding is underway across Montana and high wheat prices are encouraging producers to maximize their yields, says a Montana State University Extension soil fertility specialist.
Nitrogen is the main nutrient that most often limits wheat yields and represents a grower's largest fertilizer cost input. "Optimizing nitrogen availability should maximize yield and use fertilizer nitrogen more efficiently," says Clain Jones.
With near record fertilizer nitrogen prices and winter wheat prices, optimizing nitrogen fertilizer use is more important than ever for maximizing profit.
"Band applications of nitrogen are favored over surface broadcast applications due to increased root access, particularly in dry soil conditions," he says. Broadcast nitrogen applications can lower root zone nitrogen availability under dry soil conditions, reducing uptake and yields.
Spring nitrogen applications can result in greater yield than nitrogen applications at seeding, freeze-up or on snow, due to more chance for nitrogen losses from fall and winter applications, he notes. However, fall and spring nitrogen banding have resulted in similar winter wheat yields, Jones adds. Early spring nitrogen applications generally result in higher winter wheat yields than do late spring applications.
Split applications generally do not increase yield, Jones says. "Unless combined with other field operations, additional nitrogen applications increase overall applications costs," he says.
Summaries of winter wheat and nitrogen studies may be found at landresources.montana.edu/fertilizerfacts. Check Nos. 4, 26 and 41 on the Web site.