Last week we saw 3 consecutive nights in the 20’s with the lowest reaching 22 in some areas. Now that a week as passed, we can see the signs of damage on some of our jointing wheat.
You wouldn’t know it just from looking at the field from the truck, but when we split the stems and look inside at the developing heads, the damage is apparent. What we should see in a healthy head is a nice white color and a turgid structure. Typically we can distinguish each individual floret. See below.
The grain head below was damaged by the cold. You can see that it has lost its turgidity and looks kind of like the tip of a thin wet paint brush. It’s hard to see in the photo, but the color has turned to a pale tan. Color isn’t always the best indicator because differences can be so subtle that they are hard to see.
Here is a look at a good and bad head side by side for comparison.
These heads that are damaged won’t continue to develop, though the plants may remain green. If you are seeing a significant amount of damage in your fields, it may be wise to consult your crop insurance agent before adding any more inputs (i.e. fungicides at flag leaf). Here is a good publication describing exactly what happens to the plant when injured by cold weather. If you would like help identifying damage in your fields, please contact your local Extension Agent.