The increased application of herbicides with soil residual activity in corn and soybean production has complicated fall establishment of cover crops. Initially, the concern focused on the emergence and early vigor of cover crop stands, but has more recently been implicated by some individuals as contributing to a decrease in winter survival. As farmers explore methods for seeding cover crops even earlier in the fall or possibly inter-seeded with corn, the issue of herbicide carryover becomes an even more critical issue, says Bryan Young. The Purdue University weed scientist shares how we can make educated estimates of which herbicide and cover-crop combinations may be the most detrimental, but trial and error will prove to be the only reliable method of gaining local experience that directly relates to your farm operation.