Eat this weed!

Commonly known as Rattlesnake weed or Florida Betony, or properly known as Stachys floridana.  This is one weed that has some benefits-- you can eat the roots!  It grows about a foot tall and has white to pink flowers with purple markings.  The stems are square, as is typical of members of the mint family.
It was thought to occur only in Florida until the 1950's and was then spread by humans through the movement of turf and ornamental plants.  Even a tiny piece of the white root can start an entire new plant.  This weed is now common throughout the Southeastern U.S. and parts of California.  It is capable of producing seed but virtually all reproduction is by the tubers and root sections.
The tubers are the desirable, edible part of the plant and somewhat resemble the tail of a rattlesnake.  They are firm and white and are normally 3-4 inches long.  The tubers can be eaten raw or cooked and require no peeling.  Simply wash them off.  Raw, they are crisp and crunchy, similar to a very mild radish.  Cooked, they add a peppery flavor to whatever they are combined with.  They are often added to soups and retain their crunchy texture even when cooked.

There is a closely related plant (S. affinis) known as Crosnes or Chinese artichokes.  Many botanists contend they are the same plant, but in organic and gourmet markets in New York, Crosnes sells for up to $5 per tuber-- the equivalent of $150 per pound!!  They are served in some of the finest restaurants and priced accordingly.
Just think... those weeds in the back yard could be your next gourmet meal!  Don't plant them on purpose though--they are invasive.  Even if you harvest them regularly you won't get rid of them.  The thin roots break off easily and any piece remaining in the soil will grow a new plant.  I've been eating these for years and the number of them growing in my yard has not diminished in the least!
If you have this weed, try eating it.  You might like it!