Posted 2 July, 2026
The annual Iowa State Fair Weed Identification Contest will return to the Iowa State Fair on Friday, Aug. 14, from 9 to 11:30 a.m. in front of the Agriculture Building. The contest is supported by Iowa State University Extension and Outreach and the ISU Department of Agronomy.
Participants of all ages can test their knowledge of common weeds found in Iowa by attempting to identify real weed samples, potted and on a tabletop display. The contest requires contestants to know commonly accepted names of weeds, but they do not need to know scientific names.
The contest is open to all ages, with three distinct age divisions: future agronomists (youth under age 19), general and professional. Future agronomists will identify 20 common Iowa weeds; those in the general division will identify 30 weeds; and professionals will identify all 30, as well as five extra-challenging Iowa weeds.
Following the contest, winners from each division will be announced during the awards ceremony, held inside the Agriculture Building at 3 p.m. on Aug. 14. The top five winners in each division will receive a cash prize and a coveted Iowa State Fair ribbon.
Weeds from the contest — including their common names and interesting facts — will remain on display for the duration of the fair in the lower level of the Agriculture Building.
“This summer is off to a great start with many weeds growing in the greenhouse in preparation for the contest. We invite all plant identification enthusiasts to see how their ID skills stack up against the best,” said Meaghan Anderson, extension field agronomist at Iowa State and contest organizer. “The contest will have a variety of easy and common to very rare weedy species – start studying now!”