Linsey - Your butterflies look beautiful! I hope they go out into the big wide world to mate and then come back and lay babies on some of your milkweed!
KC - According to the website link that I listed above, and I quote:
"Butterfly and moth diseases are purchased by gardeners,vegetable farmers, forestry services, and more. Parasitiods are purchased by the hundreds and thousands and released in nature. Since none of us like to take a bite from an ear of corn and find half a caterpillar left, we can understand why farmers tend to use diseases and other sprays. In most cases these diseases are species specific and will not harm butterflies in your yard."
I suspect it may have been introduced by people here in this country to kill caterpillars and butterflies. It wouldn't surprise me if that were the case!
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