Yesterday we had a wild greens salad with dead nettles as one of the primary ingredients, thanks to one of my enterprising apprentices. Dead nettles (Lamium purpureum, Lamiaceae) is one of the first plants to flower in the southeast; sometimes even in January. Native to Eurasia, it has taken quite nicely to our fields, farms, cities, and lawns; next it will want our jobs and then destroy our way of life. The leaves and flowers can be eaten sparingly in salads or as a garnish, or cooked in soups, stir-fries etc. It’s quite pubescent (obtusely worded for hairy) so I like to mix it with other greens or cook it to mask its texture. Plants make hairs for many reasons, one of the primary ones being to deter herbivory. It works on me, and many other fellow two-legged mammals. This is a nibble plant anyhow, and not your primary potherb kind of wild green. Can you imagine cooking up a mess of peppermint? Once it starts going to seed, the calyx gets a little pokey and the salads get a little chokey.
Because it is often flowering in early spring when my classes are beginning, it often finds itself as an unsuspecting mint family dissection/nibble example. This is how I happened upon the surprising discovery that ants disperse the dead nettle seeds. Many of our native spring flowering plants have evolved with ants in an interesting seed dispersal relationship. Trillium, bloodroot, dutchman’s breeches, trout lily, wild ginger, squirrel corn are a few examples. These plants have an extra appendage on their seed called an elaiosome; it often appears as a white or translucent blob or little Mohawk. The elaiosome is a rich nutritious treat for the ant, who gladly gathers the seed, and being a social creature, takes its booty home to share with the sweet little larvae.
After the ants eat the elaiosome, they discard the seed in their trash heap, which is no Miami dump mind you. It is a nutrient-rich, well aerated, and loose-soiled plant haven. My, to germinate in an ant midden says the seed (to no one in particular). I say get out there and crawl around with some purple dead nettle and watch those ants doing their thing this spring and enjoy some good old fashioned herbivory at the same time.