Cardamine maxima (Nutt.) Wood

Large Toothwort

Habitat: By woodland streams or on calcareous wooded slopes. [Hardwood to mixed forest (forest, upland)]

Range: Southern Maine to Wisconsin, South to West Virginia and Tennessee.

Aids to Identification: This toothwort can be distinguished from the similar two-leaved toothwort (Cardamine diphylla) by the presence of three stem leaves usually arranged alternately along the stem. The rootstock is jointed (opposed to continous in C. diphylla. The flowers are white or pale purple, 1-2 cm wide.

Ecological characteristics: Very little is known about the ecological characteristics of this species in Maine. It is thought to be a fertile hybrid between Cardamine concatenata and Cardamine diphylla. The fruits are sometimes sterile and intermediate morphology.

Phenology: Flowers April - May.

Family: Brassicaceae

Synonyms: Also known as Dentaria maxima (Wood.) Nutt.

Known Distribution in Maine: This rare plant has been documented from a number of sites in Maine in the past few years.

Dates of documented observations are: 1905, 2003, 2009, 2010

Reason(s) for rarity: At northern limit of range; habitat being depleted.

Conservation considerations: Unclear how forestry practices would affect populations.