Harvest Management and Storage of Pulse Crops

The 2022 growing season was off to a cool start and saw average rainfall for most parts of the province. Hot temperatures near the end of July and early August hastened maturity in peas and lentil crops across the southern province. Chickpeas will also soon be ready. Faba beans and soybeans tend to be ready later in the harvest season. Growers may be looking for information on harvest tips to maintain premium quality pulses and insight into storage in case of pulse carry-over into the new year in anticipation of higher prices.

Harvesting pulses can be a challenge. Wind, recent rains and heavy stands can result in lodging or, in some cases, the crop completely lays over (peas). Short crops can lead to missing bottom pods or trouble feeding into the combine. Specialized pickup teeth such as duck feet, can help feed the crop and ensure headers are harvesting all of the pods and stems. Providing the field was rolled after seeding, in most cases, experienced operators with the right headers can harvest almost all the lodged or short crop. Lifters, rock dams and other aftermarket accessories can provide growers a smoother harvest experience. Flex headers with tilt options as well as draper headers and pea augers are features that seasoned pulse growers are often seeking to help with harvest. Lentils, although a shorter crop, still stand erect and are not usually as challenging as a lodged pea crop. In the case of all pulses, care should be used when threshing to minimize cracks, splits and damage to seeds. Grasshoppers are also an issue with many of them, or their insect parts, showing up in the sample. If choosing to act against grasshoppers with a late season insecticide, take note of the pre-harvest interval and choose a chemistry that will allow adequate period prior to swathing or harvesting.

Chickpeas have small beaks connected to the seed coat and require special attention to avoid separating from the seed. Harvesting of pulses can begin when the seed moisture is still above commercially dry. In the case of peas, dry at 16% moisture, experienced growers begin combining between 19-20% moisture to minimize cracks and splits. Peas, lentils, chickpeas and fabas can all be dried in aeration down to their commercially dry specifications quite rapidly and without concern.

Producers do have to pay attention to temperature while binning pulse crops. Although moisture content may be near targets, the temperature of harvested pulse crops themselves can be quite warm. Care should be taken, especially with lentils and peas harvested at ambient air temperatures over 20 degrees Celsius. Temperature and moisture are the contributing factors to growth of mold and fungi that can result in spoiling, heating, and subsequent crop quality downgrades. Conditioning, by coring the entire centre of the bin through removing two or three loads (depending on size of bin and size of trucks) can be a good strategy to ensure moisture migration following harvest does not result in spoiling at the top of the bin (winter) or the bottom of the bin (spring).

Handling of pulse crops should be done with attention, and, where possible, conveyors should be used. When using augers, ensure the motor is not running at full throttle (low to mid) and ensure the auger is full of product. This minimizes cracks and splits in the augering process. Care should be taken to avoid augering and dropping crop from high heights where possible and to minimize additional handling if at all possible.

Many farmers continue to explore the option of carrying over peas and lentils to subsequent crop years. Peas are a good option for storing longer term. Peas have lower tannins than green lentils or fabas. Over time, tannins in the seed coat cause oxidation and discolouration can occur. High tannin faba beans, Desi chickpeas, maple peas and high tannin lentils run a greater risk of oxidation if storing additional crop years, something to be aware of if considering longer term storage. Once in storage, it is important to monitor bins as sweating can occur months down the road and can lead to spoiling within areas of the bin. Pulling a few loads from the core of the bin is the prudent way to ensure your pulses are conditioned and will continue to make the grade when delivered into the future.

For more information, visit:

https://keepitclean.ca/pulses for pre-harvest intervals.

https://albertapulse.com/wp-content/uploads/2020/01/PAMI.pdf for Improved Management of Stored Pulses research from PAMI.