524 FABACEAE 



leaflets 1-2 cm. long, linear-cuneate, remotely denticulate, deeply bifid at apex, with a mucro in 

 the notch; heads small, 6-15-flowered; calyx-teeth subulate-setaceous, about equaling the minute 

 pale rose-colored corolla ; pod included, 1-seeded. 



Grassy hillsides and valleys, Upper Sonoran and Transition Zones; southern Oregon to southern California. 

 Type locality : in a ravine between Mount Diablo and the San Joaquin Valley, California. April-June. 



Trifolium bifidum var. decipiens Greene, Fl. Fran. 1: 24. 1891. (Trifolium Hallii Howell, Fl. N.W. 

 Amer. 1: 135. 1898. Trifolium Greenei House, Bot. Gaz. 41: 334. 1906.) Distinguished from the species by 

 the broader leaves which are merely retuse or rounded at the apex. Open grassy hillsides and valleys, Upper 

 Sonoran and Transition Zones; Washington to southern California, of wider range and more common than the 

 species. Type locality: San Francisco Bay region, California. 



4. Trifolium gracilentum Torr. & Gray. Pin-point Clover. Fig. 2659. 



Trifolium gracilentum Torr. & Gray, Fl. N. Amer. 1: 316. 1838. 

 Trifolium denudatum Nutt. Journ. Acad. Phila. II. 1: 152. pi. 24. 1848. 



Annual, glabrous, the stems slender, erect or spreading, 1-5 dm. long. Leaves long-petioled; 

 stipules 10-15 mm. long, ovate-lanceolate, membranous; leaflets 6-15 mm. long, obovate, emargi- 

 nate at the apex; heads long-peduncled, globose or short-ovoid, 6-10 mm. long; pedicels 1-2 mm. 

 long; flowers reflexed in age, the rachis projecting; calyx-teeth longer than the tube, subulate, 

 entire ; corolla 5-6 mm. long, well exceeding the calyx, reddish purple or light pink ; pod 

 1-2-seeded. 



Grassy slopes, Upper Sonoran and Transition Zones; a common species from British Columbia to northern 

 Lower California. Type locality: California. April-June. 



Trifolium gracilentum var. inconspicuum Fernald, Zoe 4: 380. 1894. A depauperate form, with the 

 corolla shorter than or barely equaling the calyx, otherwise closely resembling the species. Central and southern 

 California. 



5. Trifolium Palmeri S. Wats. Palmer's Clover. Fig. 2660. 



Trifolium Palmeri S. Wats. Proc. Amer. Acad. 11: 132. 1876. 



Trifolium gracilentum var. Palmeri McDermott, N. Amer. Trifol. 300. 1910. 



Annual, glabrous throughout, the stems erect, branched. Stipules lanceloate, acuminate ; 

 leaflets linear-lanceolate, 1-3 cm. long, acute and mucronate at the apex, serrulate, the teeth 

 setaceous; heads globose, 10-15 mm. broad; calyx about 5 mm. long, the tube scarcely over 1 mm. 

 long ; corolla rose-purple, 6-7 mm. long ; pods 2-seeded. 



Confined to the islands off the coast of southern California and Lower California. Type locality: Guadalupe 

 Island, Lower California. April-May. 



6. Trifolium ciliolatum Benth. Tree Clover. Fig. 2661. 



Trifolium ciliatum Nutt. Journ. Acad. Phila. II. 1: 152. 1848. Not Clarke, 1813-16. 

 Trifolium ciliolatum Benth. PI. Hartw. 304. 1848. 



Annual, pale green and glabrous, the stems erect, 2-6 dm. high, stout and often fistulous; 

 stipules 15-30 mm. long, lanceolate-acuminate; leaflets 15-30 mm. long, oblong to obovate, ob- 

 tuse, serrulate, often with a large central light-colored spot ; heads ovoid, 15—20 mm. long ; 

 flowers reflexed in age ; calyx-teeth lanceolate, acuminate, conspicuously ciliolate ; corolla pinkish 

 purple, slightly exceeding the calyx. 



Open grassy hillsides or valleys, Upper Sonoran and Transition Zones; Washington to southern California. 

 Type locality: Sacramento Valley, California. April-June. 



7. Trifolium Breweri S. Wats. Brewer's or Forest Clover. Fig. 2662. 



Trifolium Breweri S. Wats. Proc. Amer. Acad. 11: 131. 1876. 



Perennial, pubescent and glaucous, the stems very slender, often diffuse, 15-30 cm. long. 



Stipules lanceolate; leaflets 6-15 mm. long, obovate, retuse or obtuse at the apex, denticulate; 



peduncles axillary, curved at the apex in age ; heads loosely few-flowered ; flowers pedicelled, at 



length reflexed ; calyx 4 mm. long, the tube much shorter than the teeth ; corolla rose or creamy 



white, 6 mm. long. 



Open coniferous forests, Arid Transition Zone; southern Oregon to Central California. Type locality: 

 Yosemite Valley, California. May-June. 



8. Trifolium hybridum L. Alsike or Alsatian Clover. Fig. 2663. 



Trifolium hybridum L. Sp. PI. 766. 1753. 



Perennial, glabrous or very nearly so, the stems erect or ascending, 3-6 dm. high, branching, 

 often stout and succulent. Stipules ovate-lanceolate, 12-25 mm. long, acuminate, membranous; 

 leaflets 12-25 mm. long, all short-stalked, obovate, rounded and sometimes emarginate at the 

 apex, cuneate at the base, serrulate with sharp-pointed teeth ; heads globose, long-peduncled ; 

 flowers pink, 6-8 mm. long, reflexed, pedicels slender, 6-8 mm. long ; calyx-teeth subulate, about 

 equaling the tube ; corolla much exceeding the calyx-teeth. 



In meadows, naturalized from Europe; well established in Washington, Oregon, and northern California. 

 May-Oct. 



9. Trifolium repens L. White Clover. Fig. 2664. 



Trifolium repens L. Sp. PI. 767. 1753. 



Perennial, glabrous, or with scattered hairs, the stems branching from the base, creeping and 

 rooting at the nodes, 1-3 dm. long. Leaves long-petioled ; stipules 4-10 mm. long, ovate-lanceo- 

 late, acute, membranous ; leaflets 8-20 mm. long, short-stalked, obovate, emarginate or obcordate, 

 broadly cuneate at the base, denticulate ; heads long-peduncled, globose ; pedicels 2-4 mm. long ; 



