Cardamine douglassii
| Cardamine douglassii | |
|---|---|
| |
Scientific classification 
| |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Rosids |
| Order: | Brassicales |
| Family: | Brassicaceae |
| Genus: | Cardamine |
| Species: | C. douglassii
|
| Binomial name | |
| Cardamine douglassii | |
| Synonyms[1] | |
Cardamine douglassii, the limestone bittercress or purple cress, is a perennial forb that produces white to pink or purple flowers in early spring. It is native to Ontario, Canada, as well as the eastern and central United States.
Description
[edit]Cardamine douglassii has an erect unbranched stem which is 10–25 centimetres (4–10 inches) tall and sparsely to densely hairy. The basal leaves are simple, heart shaped or round, 5–15 cm (2–6 in), borne on 4–12 cm (1+1⁄2–4+3⁄4 in) long petioles. There are 3 to 8 oblong to lanceolate leaves on the stem, which are 2–5 cm (3⁄4–2 in) long and 5 to 25 millimetres (1⁄4 to 1 in) wide. The margins may be smooth or coarsely toothed.
Although colors range from purple to a purplish white, it is important to note that entirely white petals are rare among this species. The flowers are borne in a raceme and are typically born from mid-March to late April. The petals are 7 to 15 mm (1⁄4 to 1⁄2 in) long and 3 to 5 mm wide. The fruit is linear, 1.5–4 cm (1⁄2–1+1⁄2 in) long and 1.5 to 2 mm wide.[2]
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1913 botanical illustration
Distribution and habitat
[edit]Cardamine douglassii is widely distributed in Ontario and the eastern and central United States, although local distribution may be spotty. It ranges from Massachusetts west to Ontario, Minnesota, and Missouri south as far as Arkansas, Alabama, and the Carolinas. Cardamine douglassii is listed as an endangered species by the Commonwealth of Massachusetts, and as a species of special concern by the State of Connecticut.[3] In Virginia, it grows in habitats such as swamps and forests, generally with base rich soils.[4] The presence of this species is dependent on appropriate habitat, and it may be eliminated from an area by development, changes in land use, or competition with invasive species.
References
[edit]- ^ "Cardamine douglasii Britton". Plants of the World Online. Kew Science. Retrieved October 23, 2025.
- ^ "Cardamine douglassii in Flora of North America @ efloras.org". Retrieved January 30, 2014. 'eFloras (2008). Published on the Internet (http://www.efloras.org). Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
- ^ "Plants Profile for Sericocarpus linifolius (narrowleaf whitetop aster)". Retrieved January 25, 2014. USDA, NRCS. 2014. The PLANTS Database (http://plants.usda.gov)[permanent dead link]. National Plant Data Team, Greensboro, NC 27401-4901 USA.
- ^ "Digital Atlas of the Virginia Flora | Cardamine douglassii Britton". Retrieved January 25, 2014. Virginia Botanical Associates. (2014). Digital Atlas of the Virginia Flora (http://www.vaplantatlas.org)[permanent dead link]. c/o Virginia Botanical Associates, Blacksburg.