Last Friday’s frost over much of eastern and central Ontario has knocked back the corn crop, and has left the soybeans looking rough. Top pods are worst hit, as is to be expected, which could mean overall yields won’t be as impacted as feared, depending on how deep into the canopy the frost penetrated. The biggest issue going forward will be green seed levels in harvested crops.
Frost is most damaging before R7 — when the soybean seeds are green and still developing — but has to penetrate the pod and seed coat to cause damage (wrinkling and locked-in green), says Gilles Quesnel, with the field crop team for the Ontario Ministry of Agriculture, Food and Rural Affairs, meaning that the impact on actual beans can vary greatly from the amount of plant damage seen. Getting into the crop is the only way to assess the full impact of the frost damage.
Farmers with frost-affected fields may need to assess each field individually prior to harvest to minimize grade issues — a 3% greens tolerance for crush beans is common, but careful harvest or blending may be necessary to stay within that range.
Where farmers could feel the frost sting worst is on IP soybeans — tolerances for greens may be lower, depending on the contract, says Quesnel. Farmers should check their contracts for all beans and, as harvest nears, be sure to take samples and check with your elevator to see how to best manage each field.
Beans near Richmond at 7 am this morning frost lasted for over 4 hours ! pic.twitter.com/1UfN78sfFA
— Paul Hermans (@phhermans) September 19, 2014