8/3 Soybean Update

Soybean Update:


Soybeans continue to move along.  Most of them are R4 now, with a 3/4′ pod on one of the top four nodes.  A few plants are R5, where you can feel seed in the pod in the top four nodes.  R4 to R5.5 is critical for yield.  This is the time we usually consider our August window when the soybeans could use rain about every 7 days to maintain their yield potential.  There are a TON of pods and new flowers on these soybeans from top to bottom, and a nice shower would help us maintain and fill them.  Just like in corn, once seeds begin to develop, the plant will stop growing vegetatively.  That means they will be as tall as they are going to get and there will not be any more root growth either.  We aren’t quite there yet, but we are coming up on it fast.


Similar to corn, sunshine is the main driver right now, but moisture would be beneficial.  The cool night’s slow respiration and the plants are not burning sugars in order to keep cool, that means more going into seed production!


Aphid pressure has stayed in check with a few able to be found, but nothing too serious.  With the dry weather we are having, spider mites will be a concern.  There is some great info about them below for both corn and soybeans.  Normally we worry more about them in soybeans than corn (similar to aphids), but to our south there has already been a lot of pressure in corn.  This is something we will need to monitor in soybeans.  The best way to scout is shake a plant onto a piece of paper and look for the movement.  You will get other “stuff” on the paper, but the mites will move.