Soybean Late Season Management

By Jeff Blauwet, CFE Technical Agronomist

We are entering the stage of growth that we target for fungicide application on soybeans about now. If there is a developing pod 3/16” long (or about the size you can tell if it is a pollinated flower or not) on one of the top four nodes on the bean plant, we are at R3 which is the sweet spot for yield response. In our Innovate Trail system we have shown 3.7 bu/ac response average over 9 years and 20 sites of testing with the top-of-the-line fungicides. Keep in mind not all fungicides are created equal. There are cheaper single mode of action (MOA) options out there but we already have Frogeye Leaf Spot resistant to them so they should be avoided. Multiple MOA fungicides are the way to go and will last longer and be more consistent in response. We will have a chance to protect from mainly Septoria Brown Spot and Frogeye Leaf Spot in our area with several other leaf diseases that are less common; this year we are seeing more things show up that we have not seen before, though.

Insects are always a concern in beans and two that we are seeing currently are Spider Mites and grasshoppers. Both like hot dry weather and with the June we had they are here. Aphids are not really doing anything yet so they are not currently a target; they may come later but they are hard to predict. I would recommend using something that is effective on Spider Mites as a priority this year.

Foliar feed micronutrients are also a profitable option from R3 through R5 growth stages. The beans will respond well for a while as they will be busy creating and filling pods for a while. We have tested in our Innovate Trials, Max-In Beans which is a combination of several micros and have shown 2.2 bu/ac response in 7 years of testing and 13 sites. This is not a very costly add-on and if you decide to wait for aphids and have to apply later (which is when they have shown up the last few years) this is a VERY good ROI with the commodity price where we are today.

Discuss the options with your CFE Agronomist today!