Thanks, Kim-- and thanks for the link to the article. I had heard some rumblings about tropical milkweed, but this is the first good explanation I've read of it! It sounds like it's a concern primarily in regions where the winters aren't cold enough to cause the tropical milkweed to die back each year.
It sounds as though it's fine in regions where it dies back in the winter, as then the parasite is killed.
My tropical milkweed does die back in the winter and then reseeds itself the following spring.
This is a very good thing for people living in warm regions to be aware of!
