​​​​Contaminated Seed Mixes and Cover Crops

November 2017 | 8 min., 53 sec.
by Bob Hartzler
Iowa State University


​The risk of agricultural seed introducing new weed problems was thrust into the spotlight in 2016 when planting of native seed mixes resulted in the spread of Palmer amaranth into states where it previously was not a widespread problem. This presentation will help growers, commercial agronomists, and consultants better understand the seed laws intended to prevent agricultural seed from serving as a vector for the spread of weeds. Participants will learn the basics of seed laws, seed testing, and the difficulties in assuring seed supplies are weed-free. Most important, steps that can be taken to reduce risks associated with planting seeds of native mixes and cover crops will be discussed.

About the Presenter

Bob HartzlerBob Hartzler is a professor of agronomy and an extension weed specialist. He conducts research on weed biology and how it impacts the efficacy of weed management programs in corn and soybean. Dr. Hartzler also teaches undergraduate classes in weed science and weed identification.​

Contact Information:
Email: hartzler@iastate.edu


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