Rank and typification in North American dwarf cherries, and a key to the taxa

Pubescent twigs are characteristic of Prunus susquehanae, a plant of acid, sandy or rocky barrens, whereas other members of the dwarf cherry complex, mostly of alkaline or neutral substrates of prairies, lakeshores, and scree slopes, have glabrous twigs. The correlation of this character with habit, ecology, and other morphological characters provides a basis for treating P. susquehanae (= P. pumila var. cuneata) as a distinct species. Related ta xa are best treated as varieties of P. pumila. Current application of the s cientific names is confirmed. P. pumila is lectotypified by a Miller figure , but in view of its ambiguity, a supporting epitype is also selected. Lect otypes are also designated for P. besseyi and P, susquehanae. A key and con spectus are included.