When the Rain Stops…
At some point, there will be a lapse in the rain and we can all get in the fields and get to the farm work that has been stacking up. Of this long list, there are a few items that are critical for summer annual forage management.
#1- Check your stand populations. The target population for multicut summer annuals (millet, sudangrass, sorghum sudan) is 650,000 plants per acre. These crops do have significant tillering, so some loss of plants will not greatly impact forage yield. If you estimate that you have less than a 60% stand, it may be worth replanting. If the stand has not yet emerged, dig around in the soil and search for seeds. Look for rotting or signs of washing altogether. A large quantity of rotted or washed seeds may also warrant replanting.
#2- That nitrogen you applied is long gone. Any nitrogen fertilizer that had not been absorbed by the plants has likely been washed away, and the heavy rainfall has pushed the summer annuals to grow quickly. Nitrogen is important for many plant functions, but from a production standpoint it is linked to both yield and quality of summer annuals. Applying 40-60lbs/A of nitrogen is a good rule of thumb to keep those plants dark green, growing quickly, and have adequate protein for feeding livestock. If your field experienced significant washing and loss of topsoil, it may be worth adding Phosphorous and Potassium. A soil test is the best way to know how much was lost and the necessary amount to apply.
#3- Herbicide application. There is no question that weeds thrive in these warm, wet conditions that the Southeast region has seen. Take this opportunity to evaluate weed pressure and dive into weed control options. If you find that the weed pressure is so severe that it may reduce forage yield, contact your local extension agent for weed identification and herbicide options.
#4- Replant if necessary. There is still plenty of time for summer annuals to be productive. When equipment is able to get back into the fields, prepare for a timely replant. When plenty of moisture is in the ground, there are very few limitations as far as planting mid-summer. If conditions change and we get droughty weather, focus on planting larger seeds such as sudangrass and sorghum sudan. These are drilled deeper into the soil where moisture is typically preserved longer, resulting in vigorous germination.