I think as long as you only use the *Merit on the irises, most of the pollinators will not be affected very much. Especially if you have "other things" blooming at the same time. We "keep bees', so see a lot of them flitting around the flower beds, and, it's a "rare thing" to see one on an iris bloom. I think there are too many other things (fruit tree, and berry blossoms, for example) blooming that have either "more ", or "better" food value . On the "rebloom" irises (late summer / fall), the bees have less "other stuff" , and they WILL be seen on the blossoms, but, again, not in large numbers, and by then, I believe most of the *Merit has "grown out" of the plant.
Pollinator "safety " is an important consideration....whether it's insecticides, fungicides, or even fertilizers and "biologic controls" (such as "BT") is concerned....they need all the help they can get ! I suppose the only, truly "safe" thing is to use "nothing", and, in most areas of the country, if "nothing" is used....you end up, with "nothing"
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