Late planting dates, low Crop Heat Unit (CHU) accumulations, and early frost may result in situations where corn is killed by frost before it reaches the normal stage of maturity and moisture for silage. Some fields planted for grain may not mature adequately for optimum yield, moisture and quality. Farmers may be looking at salvaging these crops by harvesting or…
cold temperatures
This week’s update investigates the causes of purple wheat leaves, how we should manage herbicide applications during periods of cold air temperatures and an update on corn planting progress in the province with a refresher on planting depth. Tell a friend about the OMAFRA field crop update and subscribe to the podcast on iTunes or Soundcloud. [iframe]<iframe width=”100%” height=”166″ scrolling=”no” frameborder=”no” src=”https://w.soundcloud.com/player/?url=https%3A//api.soundcloud.com/tracks/260192881&color=ff5500&auto_play=false&hide_related=false&show_comments=true&show_user=true&show_reposts=false”></iframe>[/iframe]
Over-night temperatures on May 22 to 23 dipped to -2 to -3 oC in many parts of Ontario. Cereal crops are hardy to light frosts. Leaf tissue on plants that have not hardened off will withstand temperatures of -4 oC or lower before the cells will freeze and damage occurs, making late spring frosts of little consequence.
Various areas in the province received frost in September and there continues to be concern the impact subsequent frost will have on the soybean crop. The extent of injury will depend on the stage of development as well as the length of exposure to frost. MECHANISM Low temperatures injure plants primarily by inducing ice formation between or within cells. The…
Alfalfa frost damage can sometimes occur in the spring after growth has started, resulting in damaged growing points. Some wilting can be visible about 24 hours after frost or some yellowish or brownish discolouration 3 or 4 days later. The top of the stems will typically bend over with a “shepherd’s hook”. Damage is often minimal and plants will grow out…