Over the past several days Louisiana wheat fields were exposed to below freezing temperatures for several hours. Freezing temperatures are projected to continue through the end of the week (ending January 6). In some areas, temperatures were in the upper teens. Fortunately, wheat was in the early growth stages prior to jointing which makes it tolerant to below freezing temperatures for several hours (Table 1). Producers will probably notice leaf injury but this is superficial and the plants should grow out of this injury (Figures 1-4). In the event we experience below freezing temperatures later this growing season , table 1 contains information on the impact of specific temperatures occurring for approximately two hours on injury and wheat yield.
Most oat varieties are somewhat less tolerant of cold weather than wheat and there is substantial variation among oat varieties for degree of cold tolerance. Oat varieties sustained more leaf injury than wheat in general. However the oat varieties are also still in juvenile growth stages with growing points below the soil surface and therefore protected. Where leaves were significantly damaged by cold the plants should survive and regrow with no significant impact on yield.
For more information on freezing temperatures on wheat and oats contact your local county agent or specialist.
Table 1 is taken from Kansas State publication C-646, Injury Symptoms of Wheat Resulting from Freezing Temperatures.
Tip burn on wheat seven days after below freezing temperature (about 20 F).
Boyd Padgett and Steve Harrison
Source: Alabama and Auburn Crop Production News, Freeze Injury on Wheat