At the beginning of February, the winter wheat crop across eastern Washington was green and looking great. The mild winter weather was treating the wheat crop well. However, the recent cold weather has some farmers concerned about the survival of their winter wheat. This simple crown test can help you determine the extent of the damage.
- Dig 20 to 50 plants for testing from each concerned site, keeping
crowns intact. Select plants from representative areas of the field, especially if you suspect damage in certain areas.
- Using cool water, gently rinse soil from plants.
- Clip all the roots off within 1/8 inch of the crown.
- Clip stems about 1 to 1.5 inches from the crown — approximately where the greenish and whitish areas meet.
- Wrap the sample in dampened paper towels.
- Place sample in plastic bag and seal. Make sure the bag is sealed to prevent dehydration.
- Place sample into refrigerator for 24 hours to prevent plant shock resulting from temperature differential.
- Remove sample from the refrigerator and leave at room temperature for up to 10 days. Growth activity should be visible as soon as 24 hours.
- Examine samples for shoot growth. No regrowth indicates a dead crown. Limited regrowth can indicate an unhealthy crown. A 1- to 1.5-inch regrowth indicates a healthy crown. That may take up to 7-10 days.
View the Crown Viability Test in pdf format (pdf).