Since 2006, Ohio State University Extension has recorded presence and level of infestation of weed species by surveying soybean fields in the fall. This information informs future weed management studies, led by Weed Science State Specialist Dr. Mark Loux, and identifies which weed species pose the greatest threat. Each county’s ANR Educator drives a 80-100 mi. circular route in his or her county, observing 80-100 soybean fields to estimate levels of weed infestation…my grandpa would have summarized this protocol as “road farming.” What can I say, sometimes the simplest methods yield the most informative data.
A total of 81 soybean fields were observed in Williams County this year. Marestail was the most predominant weed, and was present in 26% of the fields observed. Marestail can act as either a summer or winter annual, and lacks seed dormancy. If you are facing marestail pressure in your fields, you may consider a fall herbicide treatment. More information may be found in the most recent C.O.R.N. newsletter by clicking the following link: https://agcrops.osu.edu/newsletter/corn-newsletter/2019-33/fall-herbicide-treatments-%E2%80%93-even-more-important-year. More general information about soybean herbicide management strategies may be found in the 2019 Ohio Weed Control Guide by clicking the following link: https://cpb-us-w2.wpmucdn.com/u.osu.edu/dist/7/3461/files/2018/12/2019-Weed-Guide-2018-1214-accessible-1gnip2o.pdf. Volunteer corn and giant ragweed were the second and third most prevalent weed species in the county. A summary of this year’s results for Williams County is below.
