Native to (or naturalized in) Oregon:
- Broadleaf deciduous tree, 30-50 ft (9-15 m), usually low branching with broad, rounded crown of delicate branches. Leaves alternate, odd-pinnately compound, 20-30 cm long, usually 7-9 leaflets (terminal leaflet largest), each elliptic to ovate, entire, bright green, petiole enlarged at base and enclosing bud. Flowers small, fragrant, white, in pendulous clusters; pods (legume) turn brown in fall.
- Sun. Well-drained soil. Tolerates alkaline and acid pH soils, native to limestone cliffs and ridges.
- Hardy to USDA Zone 4 Native from North Carolina to Kentucky and Tennessee.
- Cladrastis: from the Greek, klado, a branch, and thraustos, fragile, referring to the brittle shoots. kentukea: of Kentucky. Once known as C. lutea, with lutea (yellow), referring to its yellow wood (see below).
The Naming Hisory: Yellowwood was first named Sophora kentukea by Dumont de Courset in 1811. In 1813, Francois Andre Michaux (= Michx. f.) described the same plant as Virgilia lutea, apparently unaware of Dumont de Courset's earlier description. In 1825, Rafinesque used the name Virgilia kentuckensis, presumably based upon Sophora kentukea, though this was an incorrect spelling. In 1869, the respected dendrologist K. Koch made the new combination Cladrastis lutea based on Virgilia lutea, perhaps unaware of the earlier names used by Rafinesque and Dumont de Courset. Velma Rudd (1971, 1972) finally corrected this error and made the new combination Cladrastis kentukea based upon the earliest name for the plant, following the Botanical Rules of Nomenclature, first using the epithet kentuckea (Rudd 1971), and later correcting that to kentukea (Rudd 1972). From the excellent publication: Conservation Assessment or Yellowwood (Cladrastis kentukea (Dum.-Cours.) Rudd), INHS Technical Report 2007 (28)
- Corvallis: Central Park, west of the playground area.
- Oregon State Univ. campus: south of the CH2M-Hill Alumni Center.