Although July seems a bit early to be thinking about next year's crop, some decisions will need to be made now in order to prepare for next year. So, what kind of decisions are these? Well, residue management decisions are now being made. What you do this fall with respect to residue will greatly influence the success of your direct seeding system the following year. The start of your direct seeding program starts at the combine. This may be old hat for many of you who have been in a direct seeding farming system for many years. However, it is important to be reminded and especially to inform those just moving into the system. This is especially important for those deciding to switch into a direct seeding system next year. The SSCA Field Days at Seager Wheeler Farm at Rosthern and at the Regina site both demonstrated good residue spreading equipment. Farmers were able to see first-hand how different choppers performed and spread the residue.
So, what are the considerations when dealing with residue? The first thing to consider is stubble height. Although there has been a rule of thumb about not cutting your stubble taller than the row spacing of your implement, there is some leeway here. This rule definitely applies to hoe drills. The rule also applies when seeding into chem fallow, even with air drill or airseeders. The straw in chem fallow tends to break off at the soil surface and tall stubble can therefore become a problem. However, for air drills and air seeders, as long as the stubble is anchored, one can generally pass through taller stubble under most conditions (except wet conditions and wet clays). If you are using a disc type opener designed for direct seeding, you can cut stubble quite high and still go through it.
The next major component in residue management is how to deal with the material coming out the back of the combine. Both straw and chaff have to be adequately spread over as much of the width of cut as possible. This is usually not a major problem when straight cutting. However, double swathing can create some problems. But, there are some general guidelines that one can make here as well. If the straw can be spread to 80% of the width of cut and chaff spread to about 50% of the width of cut, this should be adequate. Straw choppers do an excellent job of dealing with long straw. Until quite recently, the factory choppers on combines were not nearly as good as the add-on types. However, there have been vast improvements in the factory chopper design and they are close the capabilities of add-on types like Redekop and Straw Storm. If choppers are not an option on your combine, it is essential to get the straw spread as wide across the width of cut as possible. Loose straw laying on the ground will cause more problems than anchored stubble will. in this case, the length of the straw coming out of the combine should be as short as possible to avoid plugging in the spring.
Different crops will produce different amounts and types of residue as well. Most pulse crops won't leave much if any stubble. However, several of the new pea varieties pod high enough to leave some stubble behind. Under dry harvest conditions, the stems of pulse and oilseeds like canola and mustard tend to be shattered so there is mostly chaff-like residue coming out the back. This must be spread adequately. In addition, some cereals like the semi-dwarf types will produce more chaff than durum or spring wheat.
If there is a real excess residue problem that hasn't been properly spread, heavy harrows can be used to help break some of it down and to spread it over a wider area. Just remember, that this operation will cause more weeds to germinate and a spring burnoff will be needed to control these weeds.
So remember, a little forethought and preparation will go a long ways towards managing the crop residue for next year's seeding. In addition, our Farmers Helping Farmers database is available to help put you in touch with other farmers that may have a piece of residue management equipment (or other direct seeding related equipment) that you are considering to purchase. Simply contact our head office, the 1-800 line or any of our regional offices.