What are some important guidelines to follow when planting my 2016 wheat crop?

Sandra L. Wick, Crop Production Agent

It will soon be time to plant your 2016 wheat crop.  Several factors can affect the wheat crop that producers have no control over especially the weather; however, management decisions such as planting date, seeding rate, tractor operations, and fertilization are areas where certain decisions can affect wheat yields.

 It is best to use a tractor speed of between 5 and 6 miles per hour in most cases when drilling wheat, depending on the amount of down pressure on the openers.  If higher speeds are used, the openers can tend to “ride up” in the soil every now and then if down pressure is insufficient. 

According K-State Research and Extension field studies, “the ideal planting depth for wheat in most cases is about 1.5 inches.” When planting early into very warm soils, it is especially important not to plant too deeply since coleoptile lengths are shorter than normal under warm conditions. On the other extreme, producers should also be especially careful not to plant too deeply when planting later than the recommended time into very cool soils. Getting a uniform seeding depth is also important. Where producers are planting into fields with heavy residue, or where there is uneven distribution of chaff from the previous crop, uneven planting depth can be a serious problem. In those situations, it is common to end up with poor stand establishment in areas of the field where the drill opener rode up over the residue or chaff, and was unable to penetrate the soil to the same depth as in other areas of the field. 

A firm seedbed is critical for successful germination.   Planting into loose, fluffy soils can be a problem where soils have been tilled repeatedly during the summer. When seeds are planted into loose soils, rains in the fall will settle the soil and leave the crowns of the seedlings too close to the soil surface. Producers that have no-till fields should also be sure that the equipment is planting deep enough to prevent the crown from developing too close to the surface.

Planting date is also another important factor that can affect your wheat crop.  In general, wheat should be planted somewhere around the Best Pest Management Planting (BPMP) date or formerly known as the “Hessian fly-free” date.  For the Post Rock Extension District, the fly free date ranges from September 29 in Jewell and Smith Counties to October 4 in Lincoln with Osborne and Mitchell counties in between those dates. This doesn’t always work according to plan, of course. Some years, the earlier-planted wheat does best and some years the later-planted wheat does best, depending on weather conditions and disease pressure during the growing season.    There may be good reasons to plant some wheat before the fly-free date, such as having considerable acreage to plant, but stand establishment and ultimate grain yields are usually best when wheat is planted around the fly-free date and before deadlines set by crop insurance. Late-planted wheat often does not develop an adequate root system before winter, and forms fewer productive fall tillers. When planting late, seeding rates should be increased by 25 to 50 percent (up to a maximum of 120 lbs./acre) to help ensure an adequate stand and compensate for the lack of tillering.

In general, producers should apply at least part of their nitrogen before or at planting time to get the plants off to a strong start. Nitrogen rates of 20-30 lbs./acre can help with fall establishment and tillering.   Starter phosphorus with the seed or band-applied close to the seed can also help with fall early growth and establishment, particularly in low-testing soils. Low soil pH can be a concern particularly early in the season when root systems are mostly near the surface, which is often an area of lower pH.   Soil tests will determine the need for pH adjustment, and potential for aluminum toxicity with the seed are potential management strategies for low pH and aluminum toxicity issues if it is too late to apply lime before seeding.

In general seeding rates for central Kansas range from 750,000 to 900,000 seeds per acre (50 to 60 pounds per acre at a rate of 15,000 seeds per pound).  Final stands should be 600,000 to 720,000 plants per acre.   However, when planting wheat late after row crop harvest, seeding rates should be increased.   It’s best to use a seeding rate of 1,350,000 to 1,800,000 seeds per acre (90 to 120 lbs. per acre) in central Kansas.  When planting more than three weeks after the Hessian fly-free date, producers should use a seeding rate of 1,800,000 seeds per acre or 120 lbs.

Watch out for potential disease issues when planting into corn residue. The risk of some diseases may be higher when wheat is planted into fields with large amounts of corn residue left on the soil surface. Fusarium head blight (scab) of wheat, for example, is caused by a fungus that is known to cause a stalk rot of corn.

Remember to be sure and control your volunteer wheat.  Even though it has gotten pretty dry out there, volunteer wheat is still managing to survive.  Volunteer wheat should be killed at least 2-3 weeks prior to the emergence of the new wheat crop to break the “green bridge” food source.

For further questions on wheat production, contact any Post Rock Extension District Office in Beloit, Lincoln, Mankato, Osborne or Smith Center.

Post Rock Extension District of K-State Research and Extension serves Jewell, Lincoln, Mitchell, Osborne, and Smith counties. Sandra may be contacted at swick@ksu.edu  or by calling Smith Center, 282-6823, Beloit 738-3597, Lincoln 524-4432, Mankato 378-3174, or Osborne 346-2521.  Join us on Facebook at “Post Rock Extension” along with our blog site at “postrockextension.blogspot.com.  Also remember our website is www.postrock.ksu.edu and my twitter account is @PRDcrops.