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Volunteer Flax (Linum usitatissimum)

Crop Impacts: Soybean and canola

Volunteer Flax 1

About Volunteer Flax:

If appropriate crop and herbicide rotation is not used in fields, volunteer plants will arise. Volunteer Flax 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 Flax is that they can compete with the desired crop in that field for that year, and contaminate the harvest.

If Flax does slip through harvest and becomes a volunteer weed in the next planting season it will most likely be killed in any cereal crops due to the herbicides used on these particular fields. It has been shown to cause problems in soybeans and canola crops. Volunteer Flax can be can be easily controlled by herbicides, however if herbicides do not kill Volunteer Flax it is extremely problematic and hard to control. Due to the thin and flimsy nature of Flax plant stems, it is very difficult to cut, hitting a large infestation is like trying to cut through ropes. Volunteer Flax will bung up equipment, and might even break knives on cutting machines.

Family: Linaceae plant family

Volunteer Flax 2 Volunteer Flax 3

Volunteer Flax Scouting:

A Flax plant is typically an annual, with very thin stems that can grow up to 2 ft. tall. It produces sky-blue flowers and grayish green leaves.

Common locations

  • - Soybeans fields
  • - Canola fields

Volunteer Flax 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.

Latin / Alternative Volunteer Flax names:

  • - Linum usitatissimum
  • - Common Flax

Additional Volunteer Flax Resources

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

http://www.wigglesworthfibres.com/products/flax/theflaxplant.html

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

http://www.encyclopedia.com/topic/Flaxseeds.aspx