last year i had a patch (in shade) that had pachysandra, had planted a large leaved heuchera and by mid summer saw much disease. i pulled out and discarded the pach. pulled out the heuch and thew away, and noticed very large slugs. in your expert opinion, could the slugs have come in on the new plant, and can they spread disease with them. i don't know what disease..Black spots on leaves and stems black. its now may 2011 and i'm seeing some of the same problems in that area. cleared everything out. i put down Sluggo slug bait.