As crops near maturity, the risk of frost is watched closely especially this year with late crops and late stages within fields. If a grower wants to cut a relatively late crop to avoid frost damage, consider the following:
- A forecast for damaging frost that could justify early swathing is in the neighborhood of -3 to -4 C. Forecasts for light frosts may not actually occur or affect the majority of the field, and thus, would not justify early swathing.
- It is important to cut at least two days before the damaging frost occurs.
- The weather during those two pre-frost days needs to be conducive to adequate dry down.
- Freezing temperatures cause ice crystals to form in water-containing tissues of the plant. As plants mature, there is less moisture within the plant, so less frost damage occurs. Click here for more information on average first fall frost in Manitoba, Saskatchewan, and Alberta.