Faba bean will mature in 110 to 130 days depending on moisture conditions. As the crop matures, the lower leaves darken and drop, and the bottom pods turn black and dry from the bottom to the top of the plant.
Faba bean will shatter if left standing until full maturity. Many producers choose to dessicate faba bean and straight combine.
If swathing is chosen it should be swathed when about 25 per cent of the plants in the field have the lowest one to three pods turning dark.
Swaths can be difficult to pick up, especially if it snows, so a light narrow swath should be used as the crop may take up to three weeks to dry.
- The uppermost pods should be fully developed and the middle pods turning to a lighter green.
- The moisture content of the most mature seeds may be over 40 per cent and the seeds in the upper part of the plant may be over 60 per cent.
Reglone is registered for desiccation on faba bean.
- Apply when 80 - 90 per cent natural defoliation occurs and when 80 per cent of the pods are brown. The top immature pods may still be green.
- Do not delay desiccation beyond the early part of September and use high water volumes for application.
- Pod shatter can occur under recurring wet and dry conditions and this is why some producers may choose to swath.
Combine when moisture content of the seed is at 18-20 per cent and aerate to 16 per cent for safe storage. Combines should be set with maximum concave clearance, high fan speed, and reduced cylinder rotor speed (300-400 rpm). Augers should be operated at low speeds to avoid splitting. Combining in the early morning may reduce seed damage if the moisture content is low.
Storage and Handling
To reduce seed coat cracking, minimize drop distances when moving faba bean seed.
Faba bean seed often respires or "goes through a sweat" after it is placed in storage. Extra care should be taken to monitor the grain inside the bin for moisture build-up or spoilage. Aeration fans can be used to cool the grain in the fall and warm it in the spring, as well as to reduce moisture condensation in the bin. Seed is more susceptible to cracking and peeling if handled at temperatures below -20°C.
If supplemental heat drying is necessary, a maximum temperature of 32°C is recommended. Drying in two stages, with a day between operations, is suggested if more than five per cent moisture is to be removed. The maximum seed moisture recommended for safe storage is 16 per cent.
For most varieties, faba bean seed will darken over time and should not be stored through two summers.
Economics of Production
The publication Crop Planning Guide - Specialty Crops includes estimates on projected costs of production and expected returns of faba bean for livestock feed.