Last weekend I visited the Paskamansett Woods in Dartmouth. The trail takes you to and across the Paskamansett River. The low lying area adjacent to the river (i.e., the floodplain), was dotted with new bright green growth. None of our native plants typically leaf out this early, so I wandered in to take a closer look. It turned out that these were the new leaves from Lesser Celandine (Ficaria verna), also known as fig buttercup. Lesser Celandine is a low growing perennial in the buttercup family (Ranunculaceae) native to Europe and western Asia. It is now considered invasive in the northeastern United States. 

In addition to its timing, Lesser Celandine can also be identified by its dark green heart shaped leaves, and when in flower (beginning in approximately mid-April), its 7-12 glossy yellow “petals” (technically, they’re “tepals”, but most people would think of these structures as petals) with a dense cluster of stamens and carpels in the center. 

Lesser Celandine falls into the spring ephemeral category, along with Canada mayflower, starflower, bloodroot, and wood anemone; by leafing out and flowering before the tree canopy fills in, these low-growing woodland plants are able to take advantage of more sunlight reaching the ground. The fact that Lesser Celandine leafs out and flowers even earlier than our native spring ephemerals has allowed this plant to become problematic in forested floodplains, where it forms extensive mats, outcompeting native species.

In addition to its advantageous timing, Lesser Celandine has another leg up against the native competition. In addition to typical fibrous roots, Lesser Celandine also has underground clusters of thick, elongated tubers, as well as in some subspecies, clusters of tiny bulblets attached to the leafstalks above ground. Both the tubers and bulbets can separate easily (e.g., disturbance by humans or animals, a high water event, etc.) and can become new plants, allowing rapid colonization of new areas. It’s no surprise then that there was a large patch of lesser celandine within the floodplain of the Paskamansett River, as erosion and flood events are effective means of dispersal, and the damp soil provides the ideal growing conditions for this plant.