Ficaria verna (formerly Ranunculus ficariaL.), commonly known as lesser celandine or pilewort,[3] is a low-growing, hairless perennial flowering plant in the buttercup family Ranunculaceae. It has fleshy dark green, heart-shaped leaves and distinctive flowers with bright yellow, glossy petals.[4][5] Native to Europe and Western Asia, it is now introduced in North America, where it is known by the common name fig buttercup and considered an invasive species.[6][7][8][9] The plant is poisonous if ingested raw and potentially fatal to grazing animals and livestock such as horses, cattle, and sheep.[10] For these reasons, several US states have banned the plant or listed it as a noxious weed.[7][11] It prefers bare, damp ground and is considered by horticulturalists in the United Kingdom as a persistent garden weed;[12][13] nevertheless, many specialist plantsmen, nursery owners and discerning gardeners in the UK and Europe collect selected cultivars of the plant, including bronze-leaved and double-flowered ones. Emerging in late winter with flowers appearing late February through May in the UK, its appearance across the landscape is regarded by many as a harbinger of spring.[12]
^USDA, NRCS (n.d.). "Ranunculus ficaria". The PLANTS Database (plants.usda.gov). Greensboro, North Carolina: National Plant Data Team. Retrieved 18 October 2015.
^Post, Angela R.; Krings, Alexander; Wall, Wade A.; Neal, Joseph C. (2009-01-01). "Introduced Lesser Celandine (Ranunculus Ficaria, Ranunculaceae) And Its Putative Subspecies In The United States: A Morphometric Analysis". Journal of the Botanical Research Institute of Texas. 3 (1): 193–209. JSTOR41972152.