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Volunteer Wheat (Triticum aestivum)

Crop Impacts: Flax and Canola

About Volunteer Wheat:

If appropriate crop and herbicide rotation is not used in fields, volunteer plants will arise. Volunteer Wheat is left over from past crops. Sometimes they appear because not all the seeds from the previous crop were completely harvested, many of their seeds can fall on the ground during harvest or they can be spread by farm equipment. If the seeds are able to survive the winter months, it has the potential to germinate and grow in the next year’s crop. The problem with Volunteer Wheat is that they can compete with the desired crop in that field for the year and contaminate the harvest.

Family: Grass family (Poacaea)

volunteer-wheat-1

Volunteer Wheat Scouting:

Wheat is an annual weed that reproduces by the release of their seed. They have a straight and smooth stem, with leaf blades that are smooth, wide and twist clockwise. The flowers the Volunteer Wheat produces sit in spikes and the lemmas can be awnless or awned, depending on the variety. They have oblong seeds that are reddish in color and are quite small. The seed life of Volunteer Wheat living in soil is about 1 to 3 years.

Common locations

  • - Flax fields
  • - Canola fields

Volunteer Wheat Control:

Prevention & Cultural Control

Make sure to give all equipment that has been used in harvest a good clean to make sure no seeds are transferred. To eliminate any chance of planting the wrong seed, segregate seed supply by trait. There are four main steps you can do to make sure you are doing your best to control the spread of unwanted plants. 1) Go over the herbicides chemistry for burn down application before planting. 2) Integrate post-harvest cultivation into your field maintenance. 3) Use control measures that can be done in non-crop areas. 4) Plant certified seeds to reduce the chance of unwanted plants from growing. That being said it is impossible to say that a bag is 100% pure seed because of the way seed production happens, and the potential movement of pollen. Overall, for managing unexpected volunteer plants in crop fields you should rotate your crops, rotate the group herbicide that is used, rotate herbicide tolerant plants, rotate the time in which the herbicides need to be applied and finally till your fields.

Chemical Control

Trying to control older and larger plants is much more difficult and time consuming, therefore timely application is critical. Herbicides will be ineffective if applied when the plant is under stress. The herbicides will have more effect right before or right after rain due to the fact that the roots of the plants are taking in water at the time, which in turn means they will be taking in the herbicide as well. Group 22 herbicides work well in controlling Volunteer Wheat, and some but not all Group 1 herbicides work as a control method as well. If you are looking for control methods of Volunteer Winter Wheat in Roundup Ready Canola, Liberty Link Canola or Clearfield Canola the herbicides used on these desired plants should work well.

Latin / Alternative Volunteer Wheat names:

  • - Triticum aestivum

Additional Volunteer Wheat Resources

http://www.croplife.ca/issues/herbicide-tolerant-volunteers

http://www.oardc.ohio-state.edu/seedid/single.asp?strId=320

http://www.depi.vic.gov.au/agriculture-and-food/grains-and-other-crops/crop-production/identification-of-cereal-seedlings

http://www.croplife.ca/wp-content/uploads/2012/02/croplife_eng_apr112.pdf

http://www.gov.mb.ca/agriculture/crops/weeds/volunteer-wheat.html

http://www.agannex.com/field-crops/volunteer-winter-wheat-management