Freeze Injury On Wheat

By Boyd Padgett and Steve Harrison

LSU AgCenter  

The impact of freezing temperatures (24oF) on wheat varies dramatically depending on the growth stage the crop is in when it occurs. Temperatures are projected to dip into the teens and 20s in central and north Louisiana for several days beginning February 11th. Fortunately, wheat is very tolerant to freezing temperatures (12oF) prior to jointing (F6) since the growing point is still below ground. Freezing temperatures on pre-jointing wheat may result in leaf injury only but this is superficial, and the plants should resume normal development (Figures 1-4).  However, damage can be severe beginning at jointing depending on the temperature and duration of the freeze event.   

Most oat varieties are less tolerant of cold weather than wheat and there is substantial variation among oat varieties for degree of cold tolerance.  Oat varieties will sustain more leaf injury than wheat in general. However, oat varieties still in juvenile growth stages (similar to wheat) with growing points below the soil surface should be protected.  Where leaves are significantly damaged by cold the plants should survive and regrow with no significant impact on yield.  If oats are growing upright with nodes visible above ground, these tillers may be killed.  It is still pretty early in the crop cycle and those varieties have time to put up secondary tillers and recover. 

Growers should wait about a week after the freeze event to assess potential damage in order for damaged tissue to become discolored and wilted.   

For more information on freezing temperatures on wheat and oats contact your local county agent or specialist.