This summer, with reduced mowing at the Windswept Cranberry Bog on Polpis Road, you may have noticed a field of towering white flowers in the fields surrounding the cranberry bogs near Stump Pond. The white spikes are the flower stalks of an unusual native wildflower called “colic-root,” “stargrass,” or “unicorn root” (Aletris farinosa). This is not to be confused with another native wildflower called unicorn root or Culver’s root (Veronicastrum virginicum), which grows in western Massachusetts and has multiple white flower spikes and whorls of leaves on the upright stalks of each plant. In contrast “our” unicorn root has a single spire of white flowers, much like a unicorn’s horn, and only a cluster of leaves at ground level, forming a star-shaped basal rosette that radiates from the base of the stem.
As you might expect from a plant with several odd-sounding common names, unicorn root is an unusual plant. Once placed in the Liliaceae (Lily Family), it’s now considered a member of the family Nartheciaceae (the Asphodel Family) by some botanists. That makes it the only Asphodel Family member native to New England. You can see the resemblance to lilies in the basal rosette of flattened light yellowish green leaves with parallel veins. Long and narrow, these leaves also look a bit like a lance-leaved plantain (Plantago lanceolata). But the flower stalk of unicorn root is a dramatic spire of white, often reaching 2-3 feet tall. Each flower on the spire (technically called a “spikelike raceme”) is tubular, and the tubes flare out into pointed lobes. Coated in a strange crumblike, mealy texture, the flowers are said to be “farinose” a term that reminds me of farina flour, a useful way of remembering a botanical term.
What about the fact that “root” is a common part of many common names for this plant? That’s because it has been harvested and specially prepared as a medicine to treat colic and other types of indigestion, along with other ailments. To parents with a baby suffering from colic, this treatment and common name would be so much more memorable than the flowers stalks’ resemblance to unicorn horns!
With its abundant flowers, surely the unicorn root attracts a variety of insects, but which ones? Apparently, this topic has not received much study, but it could be an avenue for further research to help conservationists understand native plant/insect interactions. It seems likely that the impressive floral display is an open invitation to native bees, flies, and moths or butterflies. I investigated this a bit when I visited the plants one afternoon this week, and managed to capture a single photo with an insect exploring some flowers. Can you spot the insect visitor?
Clearly this topic could use some investigation at other times of day when different types of insects are actively feeding. And there could be interesting leaf, stem, or seed eating insects as well. On Nantucket, unicorn root grows in colonies on sandy, seasonally wet fields and sandplain grassland or coastal heathland. In early summer, the seasonally soggy back field of Windswept Bog is a good location to view this species in full bloom. Considered widespread in Massachusetts, this species is extirpated (extinct) in New Hampshire, and rare in Rhode Island. Maine was believed to have lost all of its unicorn root, as it had not been recorded there in 130 years, but a field of about 300 of the plants were found there just last summer! Check out this link to the Maine unicorn root discovery from last year.
We’re lucky to have several substantial patches of unicorn root on Nantucket, where hopefully it will continue to set seed and spread for many years to come. If you have a moist, sandy, “weedy lawn” in your yard, it’s entirely possible you have some basal rosettes of this plant that have gone unnoticed, as they would be unable to send up their flower stalks due to the mowing. The basal rosettes can escape the mower blade since they grow so low to the ground, and the plant probably can produce offspring by sending out shoots. It’s worth a look, and could be a great “bonus” wildflower meadow species in your yard! Sometimes seeds of wildflowers can also remain dormant and pop up when the soil is disturbed during construction, so keep an eye out for the possibility of “Nantucket unicorns.”