By Stephanie Karhoff and Kyle Verhoff
Fall provides a great opportunity to scout and manage forage hay fields and pastures. In established stands, final harvest or intensive grazing should already have taken place to allow a fall rest period, except if planning to frost seed legumes. If needed, there is still time to soil sample and address winter annual weed concerns.
Soil test fields that will be seeded to forages next year. Apply lime as needed to adjust pH levels. Maintaining proper soil pH increases nutrient availability and will strengthen forage stands, decreasing their susceptibility to stresses like insects, diseases, or weed infestations. The 2020 Tri-State Field Crop Fertilizer Recommendations for Corn, Soybean, Wheat, and Alfalfa (Extension Bulletin 974) recommends consistently soil sampling every 3 to 4 years at no more than 25-acre samples. Lime applications are recommended when soil pH is two to three units below the desired level. In mineral soils (less than 20% organic matter) where the subsoil pH is less than 6.0, the target pH is 6.8 for alfalfa and other forage legumes. In western Ohio, or in general, where the subsoil pH is greater than 6.0, the target pH is 6.5 for alfalfa and 6.0 for other forage legumes.
Now is also the time to scout for troublesome weeds like cressleaf groundsel, poison hemlock, wild carrot, dandelion, and Canada thistle in your hay fields. Fall herbicide applications are the most effective management tool against these species. That is because winter annuals like cressleaf groundsel are at the beginning of their life cycle and more vulnerable to herbicides. Control of biennials like poison hemlock and wild carrot, and perennials like dandelion and Canada thistle, is also improved since systemic herbicides will be moved to root systems along with nutrients.