Volunteer Sunflower
Helianthus annuus

Detecting Volunteer Sunflowers in your crop fields is quite easy, due to its large and very prominent yellow flower, and yellow-brownish to green central disk. They typically grow up to 15 ft. tall with a thick stem. As a volunteer weed, it may not reach full height or stem thickness.
If appropriate crop and herbicide rotation is not used in fields, volunteer plants will arise. A Volunteer Sunflower 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 Sunflowers is that they can compete with the desired crop in that field for that year and contaminate the harvest