An item often overlooked by the first-time no-till wheat grower is spreading residue at harvest.

Most combines are equipped with some type of straw spreader, but chaff and other material coming over the cleaning shoe is seldom spread.

If we consider that wheat typically produces 100 pounds of residue per bushel of grain, a 30-bushel-per-acre wheat crop will have 3,000 pounds per acre of straw and chaff. If half of this goes through the combine, you could leave up to 7,500 pounds per acre in the strip behind the machine.

Spreading the straw will greatly reduce this density, but the chaff can still cause problems. The small windrow of chaff behind the combine will have a higher volunteer seed concentration, will potentially intercept pesticides, and will insulate the soil surface.

The cooler, wetter soil under the chaff can lead to emergence problems if you plant into it next spring. Cool, wet soil won't be a problem if you are planting wheat or canola in the fall.

However, a windrow of chaff can cause poor planter or drill performance regardless of when the crop is planted. The extra residue in a chaff windrow can reduce emergence.

If you're considering a chaff spreader, the following are questions to ask:

• How far does it spread chaff? Make sure it will cover the width of your header. If your header isn't too wide, you can probably get by with a less expensive model.

• Does it spread material uniformly? The spreader should spread chaff uniformly in both directions.

• How is the unit driven? Some units are hydraulically driven while others are belt driven. At least one type uses a fan mounted on the side of the combine to provide an air blast to spread material.

• Is it user-friendly? Can the spreader be easily adjusted? How much trouble is it to inspect and adjust the combine after the spreader is installed?

• How much does it cost, and can you get dealer support?