"I was involved in the attempted eradication of this plant from a Nature Conservancy holding north of Kansas City in the early 80s when it was first recognized as invasive. The first year, we pulled up the plants and stuck them in the notch of trees so they wouldn't accidentally re-root. That's when we found out that the plant will expend every bit of it's final energy to mature it's seeds and drop them. The next year, we collected every plant showing and carried them away for disposal. The following year, the place looked like we had never been there. It was covered with the beastie. Over the next 3 years, it was estimated that 7 tons of garlic mustard was removed before it quit coming up."To quote from this MDC link, "Garlic mustard aggressively has invaded numerous forested natural areas and is capable of dominating the ground layer in many areas. It is a severe threat to many natural areas where it occurs because of its ability to grow to the exclusion of other herbaceous species." Translation- it spreads voraciously, overwhelming the wildflowers of the forest floor.
An excellent video at this site covers its growth characteristics. In addition to tolerance to shade and a wide variety of habitats, it grows tall enough to shade out other plants and small trees. It is a prolific seed producer and these seeds are easily spread by contact with clothing, shoes and animal fur. Also, it's roots produce an allelopathic chemical that kills the fungi that many native plants and trees require for survival, clearing room for more of it's seeds to sprout.
A predator has been identified. The weevil Ceutorhynchus scrobicollis may eventually be an answer to controlling invasive garlic mustard. Information on the creature is at this site. Until then, the best description of the plant and its eradication is from the National Park Service.
It is a native European herb where it is picked in the wild or grown in gardens. Its mild garlic flavor is popular in salads and on sandwiches and the leaves are also cooked in sauces. Garlic mustard with exceptionally large leaves is said to have taproots with a horseradish taste. Excellent plant photographs as well as eating and cooking suggestions are at this web site.
We are anxious to try eating it this week- after Barbara rips it out by its roots with a blood-curdling scream and vicious grin on her lips. You are welcome to share in our bounty. Bring lots of plastic leaf bags and a sturdy back for pulling plants. Come to think of it, we'll provide the bags.