By Alyssa Essman, Ohio State University Extension
Winter annual, biennial, and perennial weeds are starting to become more noticeable up as fields green up across the state. Identification of these species can help in planning for spring burndown programs.
OSU weed science has resources to help with the identification and control of problematic overwintering weeds. Check out the YouTube page for 360 degree videos of common species such as marestail, common groundsel, field pennycress, henbit, and purple deadnettle. The wild carrot and poison hemlock videos are especially helpful as they can be difficult to tell apart in the seedling stage. More in-depth videos and fact sheets exist for dandelion, wild carrot, poison hemlock, and cressleaf groundsel. Identification of these and several other overwintering species are covered in the Common Ohio Winter Annual Weed Identification video. The Ohio State University Guide to Weed Identification and Identifying Noxious Weeds of Ohio are digital books available on iTunes or GooglePlay that can be helpful for ID and control recommendations on the go.
Each year Michigan State weed science diagnostician Dr. Erin Hill evaluates a number of plant ID apps. Results of these evaluations and considerations for their use can be found here. The best resource for weed control recommendations is the Weed Control Guide for Ohio, Indiana, Illinois, and Missouri. Several of the species mentioned in this article are featured in the “Control of Problem Weeds” section towards the back of the guide, along with other problematic overwintering weeds.