Iris Borers

Borers are the natural pest of I. versicolor. So when the European large rhizomes arrived they happily munched those. They are easier to locate in bearded irises because of the wide leaves. Look for sawtooth areas on the leaves and "goo" sort of oozing out the side. If you find them on the leaves, just pinch those leaves at that spot. If they get all the way to the rhizome, dig the plant, remove affected area, possibly give a bleach rinze and reset the plant. I have never seen the actual moth, but they do hang out around shrubbery. Iris planted out in the sun usually have fewer borers, although they will have some. You can look for reddish brown pupae in the soil when you are weeding in late summer and squash them. That is a simple care performance if you don't have a heavy infestation and don't like chemicals.