Native wild blue flag iris are up and waving. (So are the nonnative wild yellow flag iris, which will be the subject of a future post.)
The wild blue (Iris versicolor) also is called the harlequin blue flag, northern blue flag, northern iris, and poison iris. They appear more frequently in the northeastern states. Blue flags grow and fly on pole-like stems in small colonies in fields, especially those where they can get their “feet” wet:
Those blue flag feet are plant stems (rhizomes) that are systems of roots and shoots, which have been implicated in the poisoning of humans and other animals, especially calves. The plant’s sap also reportedly has been a problem for people who are susceptible to dermatitis.
However, there are reports of blue flag rhizomes being used by some Native Americans in small amounts to treat liver and kidney problems, burns, wounds, and swellings.
(Images taken in Brooklin, Maine, on June 9 and 11, 2025.)