Plants from the southern Blue Ridge Mountains and southward have relatively large basal leaves with an extended terminal lobe (T. austrina, T. nautila, T. wherryi).

In 1840, in the first critical treatment of Tiarella since Linnaeus, John Torrey and Asa Gray described two new sections:[10] Olga Lakela highlighted the section names in 1937,[11] but they have since fallen out of favor with botanists, mainly because Tiarella polyphylla is inconsistent with the dichotomy,[12] but perhaps also because there are taxa with leafy flowering stems in both western and eastern North America.

[4] In North America, there have been numerous major treatments of genus Tiarella, with taxonomies recognizing from two to six species, some including infraspecific taxa.

[35] As of October 2022[update], POWO accepts 7 species and 3 infraspecies:[2] Tiarella is native to Asia and North America.

[37][38] The range of Tiarella cordifolia sensu stricto is narrowly confined to the East Coast of the United States from Maryland through Virginia and the Carolinas into Georgia.

[15] Canada: United States: A disjunct population of Tiarella occurs in Stearns County, Minnesota but botanists believe it was introduced.

[41] It is frequent to common throughout most of its wide distribution but becomes rare at the edges of its range, in Wisconsin and the western Upper Peninsula of Michigan, Nova Scotia, New Jersey, and Mississippi.