Straight combining is a harvest technique for evenly mature canola, but it requires careful management. Also known as direct-harvesting, this harvesting technique can reduce the risk of windblown swaths and lower the green seed potential.
Factors to Consider
- Crop maturity and moisture
- Use of desiccants
- Combine settings
- Management begins early. Influenced by correct seeding methods, field uniformity is important when direct-harvesting canola. Check planting depth multiple times within a field to ensure uniform seed placement and subsequent emergence. Then, as harvest time approaches, scout fields often. Canola can be swathed until 50 percent to 60 percent of the seeds have changed color. Once the crop is past this stage, growers are restricted to direct-harvest methods. Pods of harvest-ready plants may rattle when shaken. Direct-harvested canola seed will tend to have lower harvest moisture, darker seed color, lower green seed counts and higher test weight. Direct-harvested canola may stand in fields up to two weeks longer.
- When canola is ready to harvest, it is the most important activity on the farm. Direct-harvesting begins when the canola seed is at 8 percent to 10 percent moisture to reduce the amount of green seeds and ensure proper storage. At this moisture level, there still can be a significant amount of green color remaining in the stems, so do not wait for the entire plant to become straw-colored before checking seed moisture. Seeds can lose from 1 percent to 3 percent moisture per day depending on weather conditions. Thus, delaying harvest of mature canola fields can result in greater loss due to wind, hail and shattering pods.
- Harvest aids may help. In fields where maturity varies, desiccants may be used to help even maturity. Desiccant application should happen when 60 percent to 75 percent of the seeds have changed color. Applying a desiccant too soon may result in small seed and elevated green seed counts. Other products are available that may assist in reducing pod shattering, as well. If fields have uneven maturity, greener, less mature areas may need to be combined at a later date. When using any of these harvest aids, always read and follow label instructions.
- Set combine settings as specified by the manufacturer. Generally, proper settings for direct-harvesting canola should be at 50 percent to 75 percent of the normal settings used for wheat, including speed and combining operation, cylinder speed and fan speed. Concaves should be closed tighter. Always check for loss from the combine throughout the field and if there are questions on proper operation, refer to the manufacturer’s specifications. Combining at night and morning when seed moisture is higher may help to reduce shattering depending upon the moisture in the plants.
Careful management will help to preserve canola yields when direct-combining. Harvesting in a timely manner is vital to success. For more information, contact your local Mycogen Seeds customer agronomist or trusted agronomic adviser.