fornia 



PEA FAMILY 527 



Open prairies in gravelly soil, mainly Humid Transition Zone; western Washington to northwestern Cali- 

 ia. Type locality: prairies of the Willamette and near Fort Vancouver. May-June. 



Trifolium eriocephalum var. harneyense (Howell) McDermott, N. Amer. Tnfol. 243. 1910. (Trifolium 

 harneyense Howell Fl N.W. Amer. 134. 1898.) Leaves narrowly linear, acute, otherwise scarcely to be dis- 

 tinguished from the typical species. This is the common form in eastern Oregon, extending from the Blue Moun- 

 tains to northern Nevada. Type locality: Harney Valley, Oregon. 



Trifolium eriocephalum var. arcuatum (Piper) McDermott, N. Amer. Trifol. 242. 1910. (.Trifolium 

 arcuatum Piper Bull Torrey Club 28: 39. 1902.) Plants usually glabrous throughout; leaflets narrowly ellip- 

 tical to oblong-lanceolate, obtuse; lower calyx -tooth twice as long as the ether four which scarcely exceed the 

 tube. Meadows, eastern Washington to northern Idaho. Type locality: Simcoe Mountains, Washington. 



16. Trifolium oreganum Howell. Oregon Clover. Fig. 2671. 



Trifolium oreganum Howell, Erythea 1: 110. 1893. 



Trifolium multipedunculatum Kennedy, Muhlenbergia 5: 59. 1909. 



Perennial, the stems several from a taproot, decumbent or ascending, 1-2 dm. long, herbage 

 nearly glabrous or more or less villous-pubescent. Leaflets mostly obovate to oblanceolate, about 

 1 cm long, more or less hairy below, strongly veined and mucronate ; heads about 2 cm. broad ; 

 calyx villous-pubescent, 10-12 mm. long, the subulate teeth much exceeding the tube; corolla 

 pink to purple, about 15 mm. long. 



Moist places, Transition and Canadian Zones; Washington and Idaho, south to northern California. Type 

 locality: eastern base of the Coast Mountains near Waldo, Oregon. June- Aug. 



17. Trifolium longipes Nutt. Long-stalked Clover. Fig. 2672. 



Trifolium longipes Nutt. in Torr. & Gray, Fl. N. Amer. 1: 314. 1838. 

 Trifolium Rusbyi Greene, Pittonia 1: 5. 1887. 

 Trifolium Elmeri Greene, Pittonia 3: 223. 1897. 

 Trifolium caurinum Piper, Erythea 6: 29. 1898. 

 Trifolium Covillei House, Bot. Gaz. 41: 337. 1906. 



Perennial with creeping rootstock, the stems erect, simple, glabrous or sparsely appressed- 

 pubescent, 1-4 dm. high. Stipules f oliaceous, lanceolate, entire, 20-25 mm. long ; lowest leaves 

 long-petioled, their leaflets oblong or oblong-obovate, 1-2 cm. long; stem leaves with petioles 

 shorter to somewhat longer than the leaflets ; leaflets oblong-lanceolate to linear-lanceolate ob- 

 tuse or acute, 2-3 cm. long, pallid, glabrous above, appressed-pubescent beneath; heads long- 

 peduncled, broadly cuneate at base, about 15 mm. broad; calyx 7-9 mm. long more or less 

 villous-pubescent, the subulate teeth much exceeding the tube ; corolla white, 10-12 mm. long. 



Mountain meadows, Transition and Canadian Zones; Olympic and Cascade Mountains, Washington, to 

 Idaho, south to the Sierra Nevada, California. Type locality. "Valleys of the central chain of the Rocky Moun- 

 tain ranges, and on the moist plains of the Oregon, as low as the Wahlamet [Willamette], forming extensive fields 

 of herbage." A variable species and many specific and varietal segregates have been proposed. June-Sept. 



18. Trifolium Thompsonii Morton. Thompson's Clover. Fig. 2673. 



Trifolium Thompsonii Morton, Journ. Wash. Acad. 23: 270. 1933. 



Perennial, with pale green appressed villous-pubescent herbage, the stems stout, 2-6 dm. 

 high. Lower leaves long-petioled, the upper short-petioled ; stipules lanceolate, mostly adnate to 

 the petiole, entire ; leaflets 7, linear, the central up to 7 cm. long, pungently acute, setaceously 

 denticulate; peduncles 1 or 2 on a stem, 5-15 cm. long; heads globose, many-flowered, 4-5 cm. 

 broad ; flowers purple, short-pedicelled, spreading or reflexed in age ; calyx-teeth narrowly subu- 

 late ; corolla 18-22 mm. long, the standard rounded at apex. 



Sagebrush slopes, Arid Transition Zone; Chelan County, Washington. Type locality: Swakone Creek, Che- 

 lan County, Washington. June-July. 



19. Trifolium macrocephalum (Pursh) Poir. Large-headed Clover. Fig. 2674. 



Lupinaster macrocephalus Pursh, Fl. Amer. Sept. 2: 336. 1814. 

 Trifolium macrocephalum Poir. in Lam. Encycl. Suppl. 5: 336. 1817. 

 Trifolium megacephalum Nutt. Gen. 2: 105. 1818. 



Perennial, sparsely villous throughout, on the upper surfaces of the leaves soon glabrate, the 

 stems stout, 1-2 dm. high. Leaves 5-7-foliolate, the lower long-petioled; stipules ovate-oblong, 

 about 2 cm. long, remotely serrate ; leaflets 1-2 cm. long, cuneate or obovate. obtuse, mucronate, 

 serrulate ; heads short-peduncled, short-ovoid, about 3 cm. long ; calyx villous, the lobes subulate, 

 plumose, 10-15 mm. long; corolla purplish, about 2 cm. long; pod stipitate, glabrous, 6-ovuled.^ 



Wet meadows, Arid Transition and Sonoran Zones; British Columbia and Idaho to northeastern California, 

 and Nevada. Type locality: The Dalles, Oregon. April-May. 



20. Trifolium Andersonii A. Gray. Anderson's Clover. Fig. 2675. 



Trifolium Andersonii A. Gray, Proc. Amer. Acad. 6: 522. 1865. 



Perennial, with a deep taproot, dwarf and cespitose, the branching root crown forming dense 

 leafy mat, densely silky-villous throughout. Leaves 3-5-foliolate, stipules lanceolate, acuminate, 

 entire ; leaflets 1-2 cm. long, cuneate-oblong to oblanceolate, acute and aristate, entire ; peduncles 

 often shorter than the leaves and anpearing axillary ; heads subglobose, 2-4 cm. broad, subtended 

 by a rudimentary scarious involucre; corolla purple, 12-15 mm. long, a little longer than the 

 subulate plumose calyx-teeth ; pods tomentose. 



Dry mountain slopes and valleys, Arid Transition and Canadian Zones; southern Oregon to northeastern 

 California and adjacent Nevada. Type locality: mountains near Carson City, Nevada. June-July. 



