Noland, yes it is a problem here in SE Iowa. I noticed it about five years ago in my back timber that once had loads of morels fifteen years ago. Once the garlic mustard takes over you won't see any morel mushrooms. When I finally understood what was happening, my timber was loaded with garlic mustard. It is highly invasive and the plant roots send out a toxic chemical that retards or kills all native habitat including hard wood saplings. One plant can have thousands of seeds that remain viable for five years. Once it flowers (white) it continues to seed even if it gets cut off. So when one sees the garlic mustard then it's highly possible that you will track the seed to your next site you visit. In communities north of me I notice they have volunteers come in to pull the plant during April and May at public parks and recreation areas. I feel educating the community and land owners is going to be the only way to keep on top of this evil plant.