QUIZ – Storage risk

Jay Whetter

Four questions on storage risk – including dockage, green seed, natural air drying and big bins.

1. Green chaff can be a storage risk, even if the canola seed itself is dry. In a small survey in 2023, the Canadian Grain Commission divided canola samples into seed and dockage and measured them separately. The average seed moisture for all samples was 7.5 per cent. Can you guess the average dockage moisture? 
2. It is possible to remove moisture from stored grain using natural air drying or near ambient drying (NAD), but only if that outside air has “capacity to dry.” This capacity increases with higher temperature and lower relative humidity (RH). If air is 15°C with 75 per cent RH and this air blows through canola over time, what will be the eventual equilibrium moisture content of that stored canola?
3. Farms are building bigger and bigger bins, but big bins could present air flow issues with canola – especially if the goal is sufficient airflow for drying. Prairie Agricultural Machinery Institute (PAMI) studied air movement through a 25,000-bushel bin. With canola, they found that a standard, single phase 10-hp centrifugal fan could not push air through canola when the bin was full. What did PAMI conclude was an appropriate maximum fill for that system to achieve suitable airflow for drying?
4.

Green seed is unlikely to drop much in the bin, but there is a chance it can clear in the field. It needs specific circumstances: Canola seed moisture needs to get back up to ___% with temperatures remaining at 15°C or warmer for chlorophyll-clearing enzymes to restart and produce significant curing. (Fill in the blank.)