In South Central Washington, you’ll find one of the driest wheat-growing regions in the entire world. Receiving only 6-8 inches of rain per year, many farmers in this area rely on no-till to conserve water, maximize yields and earn better profits.

Average yields can be as low as 18 bushels per acre, compared to upwards of 120 bushels per acre in the higher rainfall area of the Palouse, which is located in eastern Washington. Though margins are tight, wheat farming in this area can still be profitable with careful management.

To get the highest yield, farmers need to seed winter wheat in late August or early September after a year of fallow conditions. The resulting 13-month fallow period allows enough moisture from winter and spring rains to accumulate in the soil for fall-seeded wheat to get established.

“In this area, if you can’t plant in late summer into deep seed-zone moisture in fallow, then you have to wait for fall rains in mid-October or later,” says Washington State University agronomist Bill Schillinger.

Air Quality Concerns

Adding to the problem is the fact that blowing dust from high winds blowing across fields in this area has exceeded federal air quality standards in nearby cities a total of 20 times in just the past 10 years.

“Some of these events caused complete brownouts, zero visibility and closed freeways,” says Schillinger.

Historically, growers in this area have relied on limited spring tillage in the fallow year to break up the capillary action of the soil, slowing moisture evaporation in the seed zone during the hot, dry summer months.

Besides no-till, another option has been using an undercutter with wide, narrow-pitched, V-shaped blades that slice beneath the soil surface to interrupt capillary action in the seed zone with little soil surface disturbance.

But a major concern with any type of tillage has been the impact on dust storms due to a combination of low rainfall, high winds, limited residue cover and excessive tillage.

No-Till Still Best

In the far western part of this extremely dry area, the best option for controlling wind erosion is to practice no-till along with summer fallow and avoid tillage altogether.

“There’s no reason to till the soil when you already know in the spring that it will be too dry to plant wheat in late August,” says Schillinger.

Despite the modest grain yield potential, growing wheat in this environment can be profitable — with enough acreage and judicious use of inputs to manage costs. And even very late seeded no-till winter wheat grown on fallow ground was just as profitable as using limited tillage in much of this extremely low rainfall area.