Oclemena × blakei
Oclemena × blakei, commonly known as Blake's aster, is a hybrid of flowering plant in the aster family Asteraceae. It is native to northeastern North America. Its parent species are Oclemena acuminata and Oclemena nemoralis.
Description
The hybrid Oclemena × blakei is intermediate in appearance between its parent species. It is distinguished from its parents primarily by its leaves:| Oclemena acuminata | Oclemena × blakei | Oclemena nemoralis | |
| Plant height | 10–80 cm tall | 35–65 cm tall | 5–70 cm tall |
| Number of leaves below inflorescence | 10–22 Clustered at the summit of the stem | 20–45 | 40–75 Uniformly sized and distributed |
| Leaf blades | 15–60 mm wide | 5–24 mm wide | 2–12 mm wide |
| Leaf margins | Prominently toothed with flat margins | Small teeth | Entire and revolute |
| Flower heads | 5–46 | 2–35 | 1–15 |
| Ray flowers | White or tinged with pink | White to pink | Pink to purple, seldom white |
| Habitat | Forests | Bogs, fens, mossy lake shores |
Oclemena × blakei is sometimes confused with Eurybia radula. The latter has pale blue-violet ray flowers and 4-5 rows of phyllaries with rounded tips, whereas the former has white to pink ray flowers and 1-2 rows of phyllaries with pointed tips.
Taxonomy
Oclemena × blakei was first described as Aster nemoralis var. blakei by the American botanist Thomas Conrad Porter in 1894. Porter named the variety in honor of the botanist who collected its type specimen in Gilmanton, New Hampshire 30 years earlier. In 1920, the American botanist Homer Doliver House concluded that Aster nemoralis var. blakei "should more properly be regarded as a hybrid" of Aster acuminatus and Aster nemoralis. The resulting hybrid name Aster × blakei remained in use for the rest of the 20th century. In 1995, the American botanist Guy L. Nesom published the name Oclemena acuminata × Oclemena nemoralis., the hybrid name Oclemena × blakei is widely accepted.In the Report of the State Botanist of 1893, Charles Horton Peck described a variety of Aster nemoralis collected in northern Herkimer County, New York along with the typical variety. As described by Peck, the new variety was much larger than Aster nemoralis with a longer stem, more flower heads, and larger leaves., the name Aster nemoralis var. major is considered to be a synonym of Oclemena × blakei.
Distribution and habitat
Oclemena × blakei is native to eastern Canada and northeastern United States:Canada: New Brunswick, Newfoundland, Nova Scotia, Ontario, Prince Edward Island, QuebecUnited States: Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Rhode Island, VermontThere are unconfirmed reports that the hybrid occurs in Michigan and Pennsylvania as well.