Yes, spider mites could be a threat to your soybeans, especially if you're in one of the hotter, drier areas of the state. Yes, unless you scout on a timely basis and spray if they do take up residence in your field, you could suffer economic loss, maybe severe loss. But no, it's not a new, exotic mite.
The story was going around coffee shops that it was some special mite causing problems. John Obermeyer, Purdue University Extension specialist, says otherwise. It's the two-spotted spider mite, which he refers to as the TSSM. It's the same one that caused severe damage in many fields in 1988. It's the species that is always present, waiting for a hot, dry year when it can feed in soybean fields.
Nothing Special About This Year's Spider Mites
There are other mites, but the one you need to be concerned about is the same one that soybean farmers have always been concerned about. The entomologist notes.
Actually, miters are not insects. Instead, they belong in the spider family. They're too small to be seen with the naked eye. However, as a scouting tool, you can shake a plant that you think maybe infested over a piece of white paper. If specks appear on the paper and begin to move, then you know that you have spider mites.
Fortunately, there are insecticides that have miticide activity. If insecticide supplies become short, there are actual miticides, but they tend to be expensive. If you begin seeing signs of spider mite damage, such as yellowing and bronzing which starts at the edge of the field and goes inward, it's time to line up supplies of product and someone to apply it in case you need it.
It doesn't take long for a spider mite infestation to go form barely noticeable to full-blown. At that point, yield loss has likely already occurred.