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Mark VanGessel, Extension Weed Specialist; mjv@udel.edu
Weekly Crop Update, March 20, 2026
University of Delaware Cooperative Extension
Looking for information on herbicide selection, weed control options beyond herbicides, or weed
identification?
Check out the UD Weed Science Webpage https://www.udel.edu/academics/colleges/canr/cooperative-extension/sustainable-production/weed-science/
The website www.growiwm.org is an excellent resource on herbicide resistance and integrated weed
management.
2026 Pest Management Guide – Field Crops from Virginia Tech is a free pdf (https://www.pubs.ext.vt.edu/456/456-016/456-016.html). This is updated every year for herbicide selection and recommendations for the Mid-Atlantic region. It has the same information that is found in the Penn State Guide. The full version of Penn State Guide is available only for odd-numbered years, so the 2026 version is an abbreviated version.
Not sure what weed you have in your field? Consider using PictureThis app. It is an app that uses your phone’s camera. I find it to be quite accurate for most plants. There is a free version that is adequate for most situations.