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CONTRIBUTIONS TOWARD A FLORA OF NEVADA

cee PL 1 1957

NO. h2

* LEGUMINOSAE OF NEVADA, PART III (EXCLUSIVE OF LUPINUS, ASTRAGALUS AND OXYTROPIS) . by | C. L. \Porter

July 1, 1957

A series prepared through the cooperation of the National Arboretum and the Plant Introduction Section Crops Research Division Agricultural Research Service U. S. Department of Agriculture Plant Industry Station

Beltsville, Md.

Address all inquiries concerning this series to W. Andrew Archer, Plant Industry Station, Beltsville, Maryland

*

U. S. DEPARTMENT OF AGRICULTURE

|

ACKNOWLEDGMENT

During the course of this study which has been carried on intermit- tently for more than two years, the writer has had the benefit of opin- ions and advice of a number of specialists, chiefly on matters pertain- ing to nomenclature. Among these are Dr. Lyman Benson, Pomona College, Dr. Arthur Cronquist, New York Botanical Garden, and Dr. Reed Rollins, Harvard University. To these good people go many thanks for this assis- tance; but it should be made clear that any errors contained herein are not their responsibility but are that of the writer alone.

Except for a few critical species and occasional type specimens bor- rowed from other major herbaria, the chief basis for this study has been the Nevada specimens found in the following collections: U. S. National Arboretum Herbarium, the herbarium of the Nevada Agricultural Experiment Station, the herbarium of the University of Nevada, and the Rocky Mount-

ain Herbarium, University of Wyoming.

LEGUMINOSAE OF NEVADA, PART III (EXCLUSIVE OF LUPINUS, ASTRAGALUS AND OXYTROPIS)

by C. L. Porter * Contributions Toward a Flora of Nevada, No. h2. LEGUMINOSAE Pea Family

Herbs, shrubs, or trees, with alternate, usually compound and usu- ally stipulate leaves. Flowers mostly perfect, regular to irregular, more or less perigynous, 5-merous, the stamens numerous to definite but often 10 and monadelphous or diadelphous. Pistil 1, of 1 carpel, form- ing a legume in fruit, this sometimes modified into a loment or indehis-~ cent, and one or both sutures sometimes intruded to make the pod partly or completely 2-celled. Seeds 1 to many.

A family of about 500 genera and 1,000 species, world-wide in dis- tribution, and including many valuable food and forage plants as well as some ornamentals and poisonous plants.

The following subfamilies are sometimes treated as families.

Key to subfamilies

Flowers regular; petals valvate in buds; stamens 10 or more; leaves bip- innate oO ° e ° ° ° e ° Qo ° °o °o ° e o ° _° oO s ° c ° ° e ee MIMOSOIDEAE

Flowers more or less irregular; petals imbricate in bud; stamens 10 or less; leaves mostly pinnate or digitate, but sometimes simple or bipin- nate

Lateral petals covering the upper one in the bud.2. CAESALPINIOIDEAE

Lateral petals (wings) enclosed by the upper one (standard or banner) in the bud ° °o o °o ° ° ° ° ° oc ° ° °o °o ° ° ° ° o ° ° ° 5} o LOTO TDEAE

% C. L. Porter, University of Wyoming, Laramie, Wyoming.

Subfamily 1. MIMOSOIDEAE Mimosa Subfamily : Trees or shrubs, rarely herbs. Leaves bipinnate, with numerous small leaflets. Flowers perfect, small, spicate or capitate, regular or nearly so, usually 5-merous. Petals valvate in bud. Stamens distinct in ours, numerous or definite. The subfamily includes about 35 genera and 2000 species, mainly in

tropics and subtropics, often in dry places.

Key to genera

Plants shrubby or arborescent, spinescent; flowers in cylindrical spikes in ours; stamens numerous or 10

Spines curved, less than 5 mm. long; stamens numerous .. .1. ACACIA Spines straight, more than 5 mm. long; stamens 10... .2. PROSOPIS

Plants herbaceous, unarmeds flowers in globose heads; stamens 5 3. DESMANTHUS

1. ACACIA (Tourn.) Mill. "Acacia, Cat-claw". Gard. Dict. ed. . 17543 Willd., Sp. Pl. 21049. 1806.

Trees or shrubs, rarely herbaceous, ours armed with short, curved spines, the leaves bipinnate, with numerous small leaflets. Flowers small, regular, numerous, crowded in cylindrical spikes in ours. Sepals -5, distinct or united below. Petals )-5, distinct or united below, sometimes wanting. Stamens numerous, exserted, the filaments distinct. Pods vari- able in shape, often constricted between the seeds.

A large subtropical genus of about 300 species.

1. ACACIA GREGGII A. Gray, Pl. Wright. 1:65. 1852. (Map 1) Acacia durandiana Buckl., Proc. Acad. Nat. Scie. Phila. 1861: 453. 1861; Senegalia gregeii Britt. & Rose, N. Am. Fl. 232110. 1928.

A shrub or small tree armed with short, curved spines less than 5 mn.

long. Leaves with 2-3 pairs of pinnae, the leaflets oblong to obovate,

3-6 mm. long. Spikes of flowers 3-5 cm. long, the flowers yellowish.

Pods flat, more or less constricted between the seeds, 8-12 cm. long. Dry hillsides, Lower Sonoran zone. Clark and S Lincoln Cos. W

Texas and Sonora to S California and Baja California.

2. PROSOPIS L., Mant. 1:10. 1767. "Mesquite, Screw-bean"

Trees or shrubs, often armed with straight axillary or stipular spines, the leaves bipinnate, with numerous small leaflets. Flowers small, numerous, regular, crowded in cylindrical spikes in ours. Calyx campanulate, with very short teeth. Petals 5, distinct or wited below. Stamens 10, exserted, the filaments distinct. Pods linear and flattened, scarcely constricted between the seeds, or tightly coiled and the coil cylindrical.

About 10 species of warm regions.

Key to species

Spines developed as branches from axillary buds, not adnate to the peti- oles; fruit flattened but turgid, straights; petals distinct 1. P. JULIFLORA

Spines developed from stipules, adnate to the petioles; fruit tightly coiled into a cylinders; petals united . o « » » o » o © 20 Pe PUBESCENS

1. PROSOPIS JULIFLORA (Sw.) DC., Prodr. 2:7. 1825. 'Mesquite" (Map 2) Mimosa juliflora Sw., Prodr. 85. 1788; Acacia juliflora Willd., Sp. Pl. 41076. 1806; Mimosa salinarum Vahl, Eclog. 3235. 18073 Desmanthus salinarum Steud., Nom. Bot. Phan. 269. 1821; Acacia (?) salinarum DC., Prodr. 27. 18253 Prosopis domingensis DC., 1.c.3 Neltuma juliflora Raf., Sylva Tell. 119. 18383; Algarobia juliflora Benth. ex Heynhold, Nom. 2218. 1803 Prosopis dulcis var. domingensis Benth., Journ. Bot. Hook. 43350. 181.

A small tree with spreading branches armed with slender spines 1-) cm. long, the leaves with 1-2 pairs of pinnae and the leaflets linear-ob- long, 7-16 mm. long. Flowers greenish or yellowish, in dense cylindrical spikes or spikelike racemes 5-10 cm. long. Pods flattened but somewhat turgid, 7-20 cm. long, 10-16 mm. wide, little if any constricted between the seeds.

Nevad2 plants are referred to var. TORREYANA Benson, Am. Journ. Bot. 282751. 191. This is commonly known as Western Honey Mesquite, wirich is characterized by having foliage glabrous or glabrate, and the leaflets more than 15 mm. long.

Along desert streams and on dry flats, Lower Senoran zone. S Nye and Clark Cos. The species ranges from south-central Kansas and extreme NW Louisiana westward to S California and Mexicos also in the West Indies. The variety ranges from the Guif Coast of Texas along the Rio Grande to S and central New Mexico, Arizona, S Nevada, S California, and Mexico.

2. PROSOPIS PUBESCENS Benth. in Hook., Lond. Journ. Bot. 5282. 19)6.

"Screw-bean" (Map 3) Prosopis odorata Torr. in Frém., 2nd. Rept. 313, pl. 1. 165. Nomen confusum.3 Pe emoryi Torr. in Emory, Notes Mil. Recon. 139. 1873 Str- ombocarpa pubescens A. Gray, Pl. Wright. 1260. 18523 S. brevifolia Nutt. ex A. Gray, 1.c. as synonym; S. odorata A. Gray, Bot. Wilkes Exped. 12h75- 1854. Nomen nudums S. odorata Britt. & Rose, N. Am» Fi. 233183. 1928.

A small tree or large shrub with slender spines 8-20 mm. long, the leaves with 1-2 pairs of pinnae and the leaflets oblong, 6-10 mm. long.

Flowers yellowish, in dense cylindrical spikes 3-8 cm. long, whitish=pub-

erulent. Fruit tightly coiled, cylindrical, puberulent, 3-5 cm. long. Bottom lands, along streams in the desert, and about waterholes, often in alkaline soils. Lower Sonoran zone. Clark Co. W Texas to S

Nevada, S California, No Mexico, and Baja California.

3. DESMANTHUS Willd., Sp. Pl. hs10. 1806.

Perennial herbs, in ours, with bipinnate leaves and 6-1) pairs of pinnae bearing numerous small leaflets. Flowers small, regular, densely clustered in axillary, slender-peduncled, globose heads. Calyx campanu- late, with short teeth. Petals 5, distinct. Stamens 5 or 10, exserted, the filaments distinct. Pods linear to oblong, straight or curved, flat, few to several seeded.

About 30 species of the American tropics and subtropics, a few ex- tending northward to temperate regions.

1. DESMANTHUS ILLINOENSIS (Michx.) MacMill., Metasperm. Minn. 388. 1892. (Map 11) Mimosa illinoensis Michx., Fl. Bor. Am. 2225). 1803.3 M. glandulosa Michx., 1.c.3 Acacia brachyloba Willd., Sp. Pl. :1071. 1806.3 Desman- thus brachylobus Benth., Journ. Bot. 2358. 182.3 Acuan illinoense Kuntze, Rev. Gen. 158. 1891.

Stems 3-10 dm. high. Stipules filiform, 6-8 mm. long. Leaflets very numerous, 2-3 mm. long, oblong to linear. Stamens 5. Pods 15-25 mm. long, about 5 mm. wide, curved.

Meadows and ditch banks. Lower Sonoran zone. Clark Co., where it is apparently introduced near Las Vegas and Moapa. Ranging from Ohio to

Minnesota and North Dakota, and southward to Florida, Texas and New Mexico.

Subfamily 2. CAESALPINIOIDEAE Senna Subfamily Herbs, shrubs, or trees. Leaves simple, pinnate, or bipinnate. Flowers perfect or sometimes unisexual, more or less irregular, small or large, often showy, racemose, spicate, or rarely cymose, 5-merous. Pet- als imbricate in the bud. Stamens 10 or less, distinct or somewhat un- ited. The subfamily includes about 60 genera and 2,000 species, mainly in

tropical and subtropical regions.

Key to genera Leaves simple, not fugacious

Leaves cordate-orbicular, mostly 3-6 cm. broads branches not spines- cent e e ] e ° e e ° e e e o Ss * e e e e e e e 6 ¢ 2s hh e CERCIS

Leaves oblong to linear, 1-2 mm. broads branches spinescent 5. KRAMERIA

Leaves compound, sometimes fugacious and lacking during the dry season Calyx densely glandular; plants herbaceous . . .. 6. HOFFMANSEGGIA Calyx not glandular; plants woody or herbaceous

Plants arborescent, 1-10 m. high, with short spines about 5 mm. long e e ° * e e e es °o e e e e e e e e © e @ e e (6 e CERC TDIUM

Plants shrubby and less than m. high with longer spines, or un- armed HerbS oo « « « « © « eile isl a felitets Halle) cause sme eG Hoomn . CERCIS Le, SpovPlis. 37lerii753s "Red-bud"' Small, unarmed trees with simple, cordate-orbicular, glabrous or gla- brate leaves. Flowers appearing before the leaves, in lateral clusters, pinkish-purple. Calyx campanulate, 5-toothed. Corolla irregular, pea- like, but the keel petals larger than the others, and the wings enclos-

ing the standard. Pod oblong, flat, not constricted between the seeds.

About 7 species in North America, Europe and Asia.

1. CERCIS OCCIDENTALIS Torr. ex A. Gray, Bost. Journ. Nat. Hist. 63177. 1850. "Western Red-bud" (Map 5)

Cercis californica Torr. ex Benth., Pl. Hartwo 361. 1857«; Siliquast- rum occidentale Greene, Man. Bot. Bay Reg. Bh. 189k § Cercis nephro- phylla Greene, Rep. Spec. Nov. ll:lll. 1912.3 C. orbiculata Greene, loc.3 C. latissima Greene, 1.c.

A small tree 2.5-5 m. high, with glabrous or glabrate foliage. Leaves 3-6 cm. broad, with petioles 15-20 mm. long. Pods 5-6 cm. long, about 15 mm. wide, pointed at the apex, strongly flattened.

Canyons and slopes of the Upper Sonoran zone. Specimens from Nev- ada seen only from the Charleston Mts., Clark Co. S Utah to Arizona, S

Nevada, and the Coast Ranges and Sierra Nevada of California.

5S. KRAMERIA (Loefl.) L., Sp. Pl. ed. 22177. 1762. "Ratany"

te spinescent shrubs, in ours, or perennial herbs, grayish-pubes-~- cent, with simple, entire, exstipulate leaves. Flowers in racemes, or in ours solitary and axillary, irregular, purplish, the petals 5, small- er than the sepals, the upper 3 petals with long claws and the lower 2 petals reduced to fleshy glands. Stamens 3 or |, free or attached to the claws of the upper petals. Fruit globose or ovoid, indehiscent, 1l- seeded, covered with long slender spines.

About 20 species, American in distribution.

Key to species

Pubescence of leaves of soft, matted, curly hairs; spines of fruit barb- ec only at the apexs pedicels without stipitate glands ... 1. K. GRAYI

Pubescence of leaves strigose, the hairs stiff and straights; spines of fruit barbed on sides below the apex or sometimes barbless3; pedicels with or without stipitate glands . .o o » »o o © © © «© 2e Ke PARVIFOLIA

1. KRAMERIA GRAYI Rose & Painter, Contr. U. S. Nat. Herb. 103108. 1906. Krameria canescens A. Gray, Pl. Wright. 13)2,. 1852. Not Willd. 1825. Intricately branched spinescent shrubs 3-6 dm. high, the ED a densely silvery canescent. Leaves linear, 6-10 mm. long, covered with silvery, curly, matted hairs. Claws of the upper petals distinct. Fruit subglobose, 7-8 mm. long, its spines 3-l mm. long and barbed only at the apex. Dry, rocky ridges and desert slopes. Lower Transition zone. Clark

and SE Lincoln Cos. W Texas to S California and southward to No Mexico

and Baja California.

2. KRAMERIA PARVIFOLIA Benth., Bot. Voy. Sulph..6, pl. 1.. 18h. (Map 7). Much-branched spinescent shrubs 3-7 dm. high, the slender twigs pale or brownish. Leaves linear, mostly 5-12 mm. long, strigose with stiff, straight hairs. Claws of the upper petals united. Fruit subglobose, 6-7 mms long, its spines 4-5 mm. long and barbed along the sides or sometimes barbless. The typical phase of the species, var. parvifolia, occurs in S Baja

California. Nevada plants belong to two other varieties as follows:

var. GLANDULOSA (Rose & Painter) Macbride, Contr. Gray Herb. 56252. 1918.

Krameria glandulosa Rose & Painter, Contr. U. 5. Nat. Herb. 102108. 1906. This is probably the more common variety in Nevada, distinguished by

having the pedicels, and sometimes other parts, covered with dark stipitate glands.

Desert slopes and sandy washes, Lower Sonoran zone. Clark and Lin- coln Cos. W Texas to California, extending northward into Utah and south-

ward into No Mexico.

var. IMPARATA Macbride, Contr. Gray Herb. 56252. 1918. Krameria imparata Britt., No Am. Fl. 232199. 1930.

Distinguished by not having the dark stipitate glands on pedicels

noted above.

Desert slopes and sandy washes. Lower Sonoran zone. Clark and Lin-

coln Cos. Arizona and SW Utah to Nevada and S California, and southward

into No Mexico and Baja California.

6. HOFFMANSEGGIA Cav., Ic. 363. pl. 392, 393. 1797.

Herbaceous to shrubby plants with bipinnate and stipulate leaves. Flowers somewhat irregular, racemose, the calyx with 5 subequal lobes, covered with stipitate glands, the petals nearly equal, yellowish. Sta- mens 10, distinct, their filaments often glandular. Pods flat, dehis- cent, several-seeded.

About 20 species in North and South America and Africa.

1. HOFFMANSEGGIA DENSIFLORA Benth. ex A. Gray, Pl. Wright. 1:55. 1852.

(Map 8) Hoffmanseggia stricta Benth. ex A. Gray, Pl. Wright. 1:56. 1852.3 H. stricta / demissa Benth. ex A. Gray, Pl. Wright. 1:56. 1852.3 H. fal- caria var. stricta Fisher, Contri. U. S. Nat. Herb. 1:1). 1892.3 H. falcaria var. rusbyi Fisher, 1.c. 15.3 He falcaria var. demissa Fish- er, loco; H. falcaria var. pringlei Fisher, l1.c.3; H. falcaria var. cap- itata Fisher, 1.c.; Caesalpinia falcaria var. stricta Fisher, Bot. Gaz. 182122. 1893 s C. falecaria var. densiflora Fisher, l.c.3 C. falcaria vare rusbyi Fisher, 1.co.3; C. falcaria var. pringlei Fisher, l.c.3 C. falcaria var. capitata Fisher, 1.c.; Larrea densiflora Britt., No Am. Fl. 233311. 1930.

A perennial, decumbent herb from a deep root, the stems several from the base, up to 3 dm. long. Leaves with 5-9 pinnae each bearing 10-20 ob- long, puberulent leaflets which are rounded at the apex and very inequi- lateral at the base, mostly 3-6 mm. long, Flowers in glandular racemes, yellowish and tinged with pink, the calyx conspicuously pubescent and sti-

pitate-glandular, the corolla about 1 cm. long. Pods nearly straight,

mostly 15-0 mm. long and about 7 mm. wide, puberulent and stipitate-

10

glandular. Only a single collection seen from Nevada, collected on silty bot. tom lands, Lower Sonoran zone, 10-12 mi. N of Ripley, Clark Co., where

it is locally common. Texas to S California and central Mexico.

7.-CERCIDIUM Tulasne, Arch. Mus. Paris )):133. 18). "Palo-verde"

Large shrubs or small trees with the younger bark smooth and green, the branches bearing short spines about 5 mm. long. Leaves bipinnate, the rachis of the pinnae short and terete, the leaflets in ours )-8 mn. long, usually deciduous and lacking during the dry season. Flowers yel- low, clustered, with 5 petals and 10 stamens. Pods flattened or turgid, more or less constricted between the seeds. 7

An American genus of about 10 species in warm regions.

1. CERCIDIUM FLORIDUM Benth. ex A. Gray, Pl. Wright. 1:58. 1852. Parkinsonia florida S. Wats., Proc. Am. Acad. 11:135. 18763 P. torr- eyana S. Wats. 1.c.; Cercidium torreyanum Sarg., Gard. & Forest 2:388 1889.

A thorny shrub or small tree )-10 m. high, with a broad, irregular, open crown of crooked branches. Flowers bright yellow, in axillary ra- cemes, nearly regular, the Stenens exserted. Fruit about 7-10 cm. long.

Lower Sonoran zone. 5S and W Arizona and SE California, southward to Sonora and Baja California. Approaching S Nevada but not known to oc-

cur there except as an ornamental in Boulder City, Clark Co.

8. CASSIA (Tourn.) L., Sp. Pl. 376. 1753 "Senna"

Trees, or in ours shrubs or herbs with even-pinnate leaves having

few to many leaflets. Flowers yellowish, somewhat irregular, in ours in

HE

terminal or axillary racemes. Calyx deeply and subequally 5-lobed. Cov- olla of 5 subequal clawed and spreading petals. Stamens 10 or 5, often unequal or some of them sterile, the anthers opening by terminal pores. Pods very variable, in ours erect or ascending, turgid, nearly straight, pointed, 2-l cm. long, several-seeded.

A large genus of about 500 species, mostly in warm regions of both

hemispheres.

Key to species Plants shrubby, usually 1 m. high or more; leaf rachises prolonged into a sharp pointed spine, the leaflets fugacious, green, about 5 mm. long or le ss ° ° ° ° e ° ° e ° © e e e e e ° ° e e ° ° oe] ° e ° al e C e ARMATA Plants herbaceous, woody only at the base, mostly less than 6 dm. high, without spines; leaflets persistent, grayish-green, mostly 10-25 mn. long e ° ° ° ° ° e ° ° e e ° ° e ° e e e o ° ° e o ° e ° 2 J (G; ° COVES Tali 1. CASSIA ARMATA S. Wats., Proc. Am. Acad. 113136. 1876. (Map 9) Xerocassia armata Britt. & Rose, N. Amo Fl. 23226. 1930.

Shrubs 1 m. high or more with numerous pale green branches. Leaves exstipulate, with the rachis prolonged into a straight spine. Flowers in elongate racemes, the petals yellowish-orange. Pods indehiscent or tar- dily dehiscent, 2-) cm. long.

Dry desert slopes. Lower Sonoran zone. Clark Co. W Arizona, 5 Nev-

ada and SE California.

2. CASSIA COVESII A. Gray, Proc. Am. Acad. 73399. 1868. (Map 10) Earleocassia covesii Britt., N. Am. Fl. 23: 29. 1930. A grayish-pubescent herbaceous perennial, somewhat woody at the base, 3-6 dm. high. Leaves stipulate, with 2-3 pairs of elliptic leaflets 10-

25 mm. long and 8-15 mm. wide. Flowers in corymbose racemes, the petals

2

pale yellow. Pods dehiscent, 2-3 cm. long. Desert arroyos, canyons, and rocky slopes. Lower Sonoran zone, Clark

Co. S Nevada southward through Arizona and S California to N W Mexico.

Subfamily 3. LOTOIDEAE Pea Subfamily

Herbs, shrubs, or trees. Leaves simple or usually pinnate or digi- tate. Flowers often showy, usually papilionaceous (in Petalostemon the corolla reduced to only the banner). Petals usually 5, in the bud the up- per largest one (standard or banner) sueloaaue the two smaller lateral ones (wings), and the two lowest petals (keel) enclosed by the others and more or less united. Stamens usually 10, sometimes 5, distinct or monadelphous or usually diadelphous (9 united and 1 free), the anthers all alike or some- times of two forms.

The subfamily includes some )00 genera and 10,000 species, widely dis-

tributed in temperate and tropical regions, a few extending into the arctic.

Key to genera

1. Stamens not united by their filaments; herbs with leaves 3-foliolate and stipules large and foliaceous; flowers yellow . . 1. THERMOPSIS

1. Stamens monadelphous or diadelphous

2. Anthers of two sizes; stamens 10 and monadelphous; leaves digitate- ly 7-ll-foliolate @ e e e e e e e e e se e e e e e e e 2 o LUPINUS

2. Anthers usually all alike; stamens 10 and diadelphous or 5 and mon- adelphous; leaves mostly otherwise

3. Leaves not terminated by a tendril or bristle . Fruit not a loment 5. Herbage not glandular-dotted

6. Leaflets often 3 but sometimes more, usually denticul- ate, the teeth sometimes minute.

13

7. Terminal leaflet petiolulate, the leaves pinnately 3- foliolate; flowers racemose or spicate, the corolla deciduous

8. Pods straight; flowers white or yellow, in elong- gate racemeS so « o « « e e e e « 3¢ MELILOTUS

8. Pods curved or coiled; flowers purple or yellow, in short, dense racemes or capitate clusters . MEDICAGO 7. Terminal leaflet not peticlulate, the leaves digitate- ly 3-several-foliolates; flowers in dense, short spikes or capitate clusters, the corolla persistent 5. TRIFOLIUM 6. Leaflets entire, 1 to many 9. Flowers umbellate or solitary ...... 6. LOTUS

9. Flowers racemose

‘10. Stems woody throughout, the plants arborescent 7. ROBINIA

10. Stems herbaceous or woody only at the base 11. Stipules a pair of short spines .6. PETERIA 11. Stipules not spinescent 12. Calyx subtended by a pair of small deci- duous bractlets; tall introduced plants with reddish flowers and papery-inflated, stipitate pods ... . 9+ SPHAEROPHYSA 12. Calyx not subtended by bractlets 13. Keel of corolla blunt, or if beaked the stems sprawling and leafy ; pod never with only the ventral (upper) suture intruded . . 10. ASTRAGALUS 13. Keel of corolla with an abrupt beak: plants usually scapose; pod with only the ventral (upper) suture intruded 11. OXYTROPIS 5. Herbage glandular-dotted

14. Fruit covered with stiff hooked prickles (or an intro-

14

duced species with fruit only glandular); flowers white or blue, in dense racemes or spikes; tall co- arse herbs with pinnately 11-19-foliclate leaves, the leaflets 7-30 mm. broad. . o » « « 12. GLYCYRRHIZA 1h. Fruit not prickly; leaves and leaflets not as above 15. Fertile stamens 9-10

16. Leaves digitately 3-5-foliolate or pinnately 3-foliolate oO 10" (OL TGs (eu) 6. Le, Ve asia PSORALEA

16. Leaves odd-pinnate with several leaflets, or simple, or plants spiny and leafless 1h. DALEA

15. Fertile stamens 5, alternating with ) petaloid staminodes 0°. /.%'.. 1s) 0). “S155 PELALOSTEMON

. Fruit a loment, constricted and separating between the seeds

17. Leaves odd-pinnate; perennial herbs without spines 16. HEDYSARUM

17. Leaves simple; low shrubs with axillary spines 17. ALHAGI

3. Leaves terminated by a tendril or bristle

18. Stigma terminal, a tuft of hairs on the end of the style 18. VICIA

18. Stigma lateral, the hairs on one side of the apical port- Henvofrtherstyleleieishetlisiw ee le oo §=6¢ LIS ELATHYRUS 1. THERMOPSIS R. Br. in Ait., Hort. Kew. ed. 2, 3:3. 1811. "Golden Pea" Perennial rhizomatous herbs with trifoliolate leaves, ours having conspicuous foliaceous stipules. Flowers yellow, in terminal or axillary bracteate racemes. Calyx-tube campanulate, bilabiate, the upper lip about half the length of the tube. Corolla papilionaceous, about 1 cm. long. Stamens 10, distinct. Pods sessile or nearly so, linear, straight in ours, not constricted between the seeds, ascending in ours, }-5 cm. long, 5-6 mm.

broad, several-seeded.

About 17 species, 9 in North America and 8 in N and E Asia.

15

1. THERMOPSIS MONTANA Nutt. in T. & G., Fl. N. Am. 1:388. 180 (Map 11) Thermopsis stricta Greene, Pl. Baker. 323k. 1901:3 IT. angustata Greene, 1eCe

Stems erect, -7 dm. high, usually somewhat branched above, glabrous or nearly so. Leaves with broadly to narrowly lanceolate stipules 2-l; cm. long, and linear-lanceolate to oblanceolate leaflets 3-5 cm. long. Racemes mostly 7-20 cm. long, bearing flowers about 2 cme long. Pods appressed to the rachis, villous.

Common along streams and in meadows or aspen woods, Transition and

Boreal zones. Mainly in the N half of Nevada. Montana to E Washington,

and southward to Colorado, Utah and Nevada.

2. LUPINUS L. "Lupine" This genus has been treated by David B. Dunn in Contr. Fl. Nevada No. 39, April 6, 1956.

3. MELILOTUS Mill., Gard. Dict. ed. ). 175). "Sweet-Clover" Annuals, in ours, with pinnately 3-foliolate, denticulate leaves and small white or yellow flowers less than 6 mm. long in slender racemes. Calyx-teeth subequal. Corolla papilionaceous, the standard obovate, the wings oblong, and the keel obtuse. Stamens diadelphous. Pod ovoid, straight, reflexed, dehiscent or indehiscent, and 1-2-seeded.

About 20 species, native of the Old World.

Key to species

Corolla white; pods inconspicuously reticulate but not rugose 1. M ALBA

Corolla yellow; pods rugose

16 Flowers about 5 mm. long; leaflets neither truncate nor retuse, broad- est near the middle; plants mostly 10-20 dm. high. 2. M. OFFICINALIS Flowers about 2.5 mm. long; leaflets often truncate or retuse at the apex, broadest above the middle; plants mostly 2-7 dm. high 3. M. INDICA 1. MELILOTUS ALBA Desr. ex Lam., Encycl. :63. 1797. "White Sweet-clover"' Melilotus vulgaris Willd., Enum. Hort. Ber. 790. 1809. Plants glabrate, erect, 1-2 m. high. Leaflets mostly 1.5-3 cm. long, 5-10 mm. wide. Racemes mostly 6-10 cm. long. Widely planted and naturalized, meadows and roadsides. Native of Eurasia. 2. MELILOTUS OFFICINALIS (L.) Lam. Franc. 2:59). 1778. "Yellow Sweet-clover" Trifolium melilotus officinalis L., Sp. Pl. 765. 1753. Very similar to the preceding, but the flowers yellow and the pods rugose.« Widely planted and naturalized, meadows and roadsides. Native of

Eurasia.

36 MELILOTUS INDICA (L.) All., Fl. Ped. 1:308. 1785. "Indian Melilot" Trifolium melilotus indica L., Sp. Pl. 765. 1753. Plants relatively smaller than the preceding two species, less than 7 dm. high, the yellow flowers about half as long and the leaflets relat- ively broader. Occasionally weedy or naturalized; specimens seen from Lyon and Nye

Cos. Native of the Mediterranean region.

Ly

4. MEDICAGO L., Sp. Pl. 778. 1753. "Alfalfa, Medic" Annuals or perennials with pinnately 3-foliolate, denticulate leaves, and small dark blue, purplish, or yellow flowers in dense short heads or racemes. Calyx-teeth subequal. Corolla papilionaceous, the standard obovate or oblong, the wings oblong, and the keel obtuse. Stamens dia- delphous. Pod curved or coiled, reticulate or sometimes spiny, indehis- cente Seeds few or one.

About 50 species of the Mediterranean region, Europe, and W Asia.

Key to species

Flowers dark blue or purplish; plants perennial with mostly erect stems 1. M. SATIVA

Flowers yellows; plants annual or sometimes perennial with low, sprawling or ascending stems

Pods without spiny processes y 1-seeded, black at MADE Pig only the ti ip co ile da ° o e ° °, ° °o e ° e ° e e ° ° oe ° ° ° ° es 23 » LUPULINA

Pods with spiny processes on either side of the keeled edge, several- seeded, green at maturity, the whole pod in 2-3 tight coils 3. M. HISPIDA 1. MEDICAGO SATIVA L., Sp. Pl. 778. 1753. "Alfalfa" Medicago media Pers., Syn. Pl. 22356. 1805; Medica media Fourr., Ann. Soc. Linn. Lyons 2, 162359. 1868.

Erect or sometimes decumbent, branching perennial up to 1 m. high, glabrous or nearly so at maturity. Leaflets oblanceolate to obovate, 1.5-3 cm. long, denticulate around the apex. Flowers in short dense spike-like racemes 1-3 cm. long, the corolla about 8 mm. long, dark blue Or purplish. Pods with 1-3 turns in the spiral coil, puberulent.

Widely planted as a forage crop and naturalized around cultivated

areas and roadsides. Native of Asia.

18

22 MEDICAGO LUPULINA L., Spe Pl. 779. "Black Medic, Nonesuch" Medica lupulina Scop., Fl. Carn. ed. 2, 2288. 1772.

Procumbent, branching annual or sometimes perennial, the stems up to 8 dm. long. Leaflets obovate to suborbicular, cuneate at the base, 8-15 mm. long, the apex denticulate, pubescent especially Seeder with rather long appressed hairs. Flowers in capitate or short-cylindric spikes 1 cm. long or less, these becoming somewhat elongated in fruit, the corolla 2 mm. long or less, yellow. Pods reniform, only the tip coiled, turning black at maturity, l-seeded, sparsely glandular-puberulent.

Widely introduced and often becoming weedy. Native of Eurasia.

3. MEDICAGO HISPIDA Gaertn., Fruct. 2:39. 1791. "Bur-clover" Medicago denticulata Willd., Sp. Pl. 3s1hih. 1800.

Annual or winter annual with glabrous or sparsely pubescent foliage, with several spreading or ascending branches from the base. Leaflets obo- vate or obcordate, cuneate at the base, 6-15 mm. long, sharply denticu- late. Flowers yellow, about ) mm. long. Fruit spirally coiled, spiny, h-6 mm. in diameter, bur-like, green at maturity.

No specimens from Hevada have been seen, but the species is report- ed by Billings (Univ. Nevada Agr. Ext. Service Bull. 89257. 191) as ap- pearing spontaneously in parts of Nevada in wet years. Native of the Med-

iterranean region and widely naturalized.

5. TRIFOLIUM L., Sp.’ Pl. '764.°1753. "Clover" Annual or perennial herbs with digitately 3-9-foliolate leaves hav- ing prominent adnate stipules and usually denticulate leaflets. Inflor-

escence capitate or short-spicate, usually pedunculate, usually many-

19

flowered (in T. monanthum 1-6-flowered), and with or without a subtend- ing involucre of united or sometimes distinct bracts. Calyx with 5 sub- equal or somewhat unequal teeth, persistent. Corolla papilionaceous, white, yellow, purplish, or reddish, usually persistent. Stamens diadel- phouse Pod straight, membranaceous, usually included in the calyx, l- several-seeded, dehiscent or indehiscent.

About 300 species, chiefly in the north temperate zone.

Key to species

1. Leaflets mostly 5-7

2. Herbage densely shaggy-villous; leaflets subentire; heads 2 cm. long or less e e e e ° e ° ° e e e e e e ° e e ul e T e ANDERSONIT

2. Herbage short-pubescent; leaflets conspicuously denticulate; heads mostly 3-5 CMe long O86) ©; 6 > @ 2 OPO Or 0) 8s 2. Te MACROCEPHALUM

1. Leaflets mostly 3, occasionally )-5

3. Heads closely subtended by 1 or 2 leaves, subsessile; flowers red- dish or purplish; introduced species . « « « o « e3« To. PRATENSE

3. Heads not subtended by leaves, the peduncles well developed; flow- ers white or yellowish to pinkish, never reddish; native or intro- duced species.

h. Heads not involucrate

5. Flowers distinctly pedicellate in the head; calyx glabrous; introduced species

6. Corolla pink; stems ascending .... . el. T. HYBRIDUM 6. Corolla whites; stems creeping . . ». « « « « 5« T. REPENS

5. Flowers sessile or subsessile in the head; calyx pubescent; native species

7. Leaflets 3-5, sharply denticulate, mostly less than 3 cm. long, ovate or obovate to ellipticals; plants subacaules- cent, the peduncles not produced on elongate leafv stems

6. T. GYMNOCARPON

20

7. Leaflets 3, inconspicuously denticulate to subentire, mostly more than 3 cm. long, at least the upper leaves with nar- rowly elliptical to linear leaflets; plants caulescent, the peduncles produced on elongate leafy stems

8, Calyx-teeth long-villous on each side so as to appear plu- mose3 flowers reflexed due to curvature of the base of the flower and sometimes the whole head inverted due to curvature of the apex of the peduncle.7. ERIOCEPHALUM

8, Calyx-teeth not appearing plumose, the pubescence shorter and more appresseds flowers erect or spreading, or if re- flexed the flowers not curved at the base.8. LONGIPES

4. Heads involucrate

9. Flowers 1-3 or occasionally up to 6 in each heads involucre small, with 3-9 lanceolate lobes . . . » 9. T..-MONANTHUM

9. Flowers many in each heads involucre a conspicuous several- lobed disc or cup

10. Calyx bladdery-inflated, reticulate-veined, and enclosing the corolla at maturitys introduced species. 10. T. FRAGIFERUM

10. Calyx neither bladdery-inflated nor reticulate-veined, not enclosing the corollas native species

ll. Teeth of calyx ternately parted into divaricate setae ll. T. CYATHIFERUM

ll. Teeth of calyx entire or sometimes bifid, without di- varicate setae

12. Flowers about 1 cm. long or morés rhizomatous per- ennigls 946 © © © © © © o Lde FT. WILLDENOVII

12. Flowers less than 1 cm. long; annuals 13. Herbage villous; clayx-teeth with broad scar- ious margins; involucre equaling the corollas or longer . 6 « © o o L3e To MICROCEPHALUM 13. Herbage glabrous; calyx=teeth without scarious

margins: involucre shorter than the corollas lh. T. VARIEGATUM

1. TRIFOLIUM ANDERSONIT A. Gray, Proc. Am. Acad. 63522. 1865. (Map 12) Densely villous, caespitose perennial 1 dm. or less high, from a deep

taproot and branching root-crown. Leaves mostly 5-foliolate, the leaflets

21

cuneate-oblong or oblanceolate, acute, subentire. Peduncles equaling or

shorter than the leaves. Heads subglobose, 2-3 cm. broad, subtended by a

rudimentary scarious involucre. Calyx-teeth subulate, plumose. Corolla

purplish or pink, 12-15 mm. long.

Dry hills and valleys, with sagebrush, pinyon, and yellow pine. Cal- ifornia and W Nevada. The type came from near Carson City, Ormsby Co., Nevada. Sterile plants might well be taken for a lupine.

2. TRIFOLIUM MACROCEPHALUM (Pursh) Poir. in Lam., Encycl. Suppl. 5:336. 1817. (Map 13) Lupinaster macrophyllus Pursh, Fl. Am. Sept. h79. 1814.3 Trifolium meg- acephalum Nutt., Gen. 2:105. 1818.

Sparsely villous perennial 1-2 dm. high, from a branching woody root. Leaves mostly 5-7-foliolate, the leaflets cuneate-obovate, obtuse or trun- cate and mucronate at the apex, their margins sharply denticulate. Ped- uncles exceeding the leaves. Heads ovoid, about 3-6 cm. long. Involucre vestigial. Calyx-teeth subulate, plumose. Corolla purplish or pinkish, about 2 cm. long.

Meadows and valleys of the Transition and Upper Sonoran zones, most- ly between h ,000 and 5,000 ft. British Bedunpie and Idaho southward to

NE California and NW Nevada.

3. TRIFOLIUM PRATENSE L., Sp. Pl. 768. 1753. "Red-clover" Sparingly villous ascending or erect, branching perennial or bien- nial 2-6 dm. high, from a deep woody taproot. Leaves 3-foliolate, the leaflets elliptical to ovate, mostly 2-); cm. long and 1-2.5 em. broad, obtuse or emarginate, sparingly pubescent, very obscurely denticulate.

Peduncles very short, the heads subsessile and subtended by 1 or 2 leaves

22

whose broad stipules resemble an involucre but true involucre lacking. Heads globose or ovoid, 2-3 cm. broad. Calyx-teeth subulate, villous. Corolla reddish or purplish, about 12-15 mm. long.

Widely planted as a forage crop and sometimes naturalized. Native

of Burasia.

). TRIFOLIUM HYBRIDUM L., Sp. Pl. 766. 1753. "Alsike Clover"

Glabrous or nearly glabrous, erect or ascending perennial up to about 5 dm. high, from a taproot and branching root-crown. Leaves 3-foliolate, the leaflets cuneate-obovate, up to 25 mm. long, rounded at the apex, sharply serrulate. Peduncles equaling or exceeding the leaves. Heads globose, without an involucre, mostly 1.5-2 cm. broad, the flowers on short slender pedicels and soon reflexed. Calyx-teeth narrowly lanceo- late to subulate, glabrous. Corolla pink, 6-8 mm. long.

Commonly cultivated and becoming naturalized. Native of Europe.

5. TRIFOLIUM REPENS L., Sp. Pl. 767. 1753. "White Clover" Glabrous or sparingly pubescent, creeping perennial, the stems root-

ing at the nodes, 1-3 dm. long. Leaves 3-foliolate, with petioles up to 8 cm. long, the leaflets cuneate-obovate to obcordate, mostly 10-20 mm. long, sharply serrulate. Peduncles usually exceeding the leaves. Heads globose, without an involucre, mostly 1.5-2.5 em. broad, the flowers on short slender pedicels, reflexed in age. Calyx-teeth lanceolate-acumin- ate, glabrous. Corolla white, 7-10 mm. long.

Commonly cultivated and widely naturalized. Native of Europe.

6. TRIFOLIUM GYMNOCARPON Nutt. in T. & G, Fl. N. Am. 12320. 1838. var.

PLUMMERAE (S. Wats.) Martin, Bull. Torr. Club 73:368. 196. (Map 1)

ae

Trifolium plummerae S. Wats., Bot. Calif. 2:0. 1880; T. plummeri Lemmon ex Lojac., Nuov. Giorn. Bot. Ital. 153162. 1883; 1. gymnocar- pon f. plummerae McDermott, N. Am. Sp. Trifol. 192. 1910.

Strigose, subacualescent, caespitose perennial less than 1 dm. high, from a deep woody taproot and a branching caudex. Leaves 3-5-foliolate, the leaflets pale green, oval or elliptic, about 6-10 mm. long, promin- ently strigose beneath and sparsely strigose above, sharply denticulate. Peduncles shorter than the leaves. Heads globose or hemispheric, 1-2 cm. broad, 3-12-flowered, without an involucre, the flowers erect or spread- ing. Calyx-teeth broadly subulate, strigose. Corolla cream-colored or pinkish, 6-9 mm. long.

Dry hills and slopes, often in clayey soils, with sagebrush and pin- yon-juniper, ascending to 10,000 ft., and present throughout most of Nev- ada. “The type came from "Peaks above Pyramid Lake, Nevada."

This variety differs from the typical var. gymnocarpon in having a more acualescent habit and leaflets strigose above instead of glabrous. It ranges from SW Montana to NE Oregon, and southward to W Wyoming, NW Colorada, Nevada and NE California. The range of var. gymnocarpon is more to the eastward. .

A related species, Trifolium lemmonii S. Wats., Proc. Am. Acad. 11: 127. 1876. is listed for western Nevada by Abrams (Ill. Fl. Pacif. States 22530. 194.) but no authenticating specimens have been seen by the writ- er. It has the general aspect of T. gymnocarpon but the flowers are re- flexed and the stems often a little taller and the peduncles tend to arise from leafy stems. It may occur on the eastern slope of the Sierra Nevada

along the Nevada border.

2h 7. TRIFOLIUM ERIOCEPHALUM Nutt. in T. & G., Fl. N. Am. 12313. 1838. var. CUSICKII (Piper) Martin, Madrono 82156. 196. (Map 15) Trifolium arcuatum var. cusickii Piper, Bull. Torr. Club 29:61. 19023 T. harneyense Howell, Fl. N. W. Am. 13134. 1897-3 T. arcuatum var. har- neyense McDermott, N. Am. Sp. Trifol. 231. 1910, fT. tropicum A. Nels. Bot. Gaz. 54209. 1912.

Villous, erect or spreading perennial 5-5 cm. high, the stems bran-~ ching from the summit of a deep root. Leaves 3~-foliolate, the leaflets mostly narrowly lanceolate to linear, 2-8 mm. wide, 30-60 mm. long, acute, and with irregularly and sharply denticulate margins. Peduncles exceed- ing the leaves. Heads subglobose to oval, without an involucre, many- flowered, 15-30 mm. broad, the flowers reflexed due to bending of the apex of the peduncle. Calyx-teeth narrowly subulate, 2-5 times as long as the tube, villous with long diverging hairs so as to appear plumose. Corolla yellowish, pink, or purplish, 8-16 mm. long.

The species is variable, ranging from S Washington southward to Utah, N Nevada, and N California. Four varieties are recognized by Martin (Mad- rono 8:152-157. 196), but only the above variety is known to occur in Nevada. It is distinguished by narrow, usually linear leaflets, and ovar- ies )-5-ovuled and 1-3-seeded.

Moist meadows and open woods at about 000-7000 ft. in the Transition

Zones E Oregon, N Nevada and SW Idaho.

8. TRIFOLIUM LONGIPES Nutt. in T. & G., Fl. N. Am. 12314. 1838. Glabrous to moderately pubescent, erect, branching perennial 1-) dm. high, from a creeping rhizome or sometimes from a taproot. Leaves 3-fol-

iolate, the leaflets variable in shape but mostly elliptical to broadly

25

or narrowly lanceolate, 12-0 mm. long, rounded or usually acute at the apex, usually finely denticulate but sometimes subentire. Peduncles ex- ceeding the leaves. Heads subglobose to ovate, without an involucre, many-flowered, mostly 1-2 cm. broad, the flowers erect orreflexed. Calyx - teeth narrowly subulate, 2-3 times as long as the tube, moderately to sparsely villous, the hairs ascending. Corolla ochroleucous, purplish, or pinkish, 8-1); mm. long.

A highly variable species ranging from Montana to Washington, and southward to Colorado, Arizona, and southern California. Nevada plants

may be referred to the following varieties:

var. LONGIPES (Map 16) Trifolium rusbyi Greene, Pittonia 1:5. 1887.3 T. elmeri Creene, l.c. 3: 223. 1897.5; T. caurinum Piper, Erythea 6:29. 1898.3; T. pedunculatum Rydb., Bull. Torr. Club 30225). 1903.3 T. covillei House, Bot. Gaz. 1:337. 1906.

Flowers erect or ascending, usually purplish or pinkish, 8-10 rm. long; aerial portion of plants usually 1-3 dm. high.

Meadows and stream banks at 6000-9000 ft. in the Transition and Can- adian zones of the Sierra \'svada of W Nevada. Idaho and Washington south-

ward to S California.

var. REFLEXUM A. Nels., Wyo. Expt. Sta. Bull. 28:9). 1896. (Map 16) Trifolium rydbergii Greene, Pittonia 3:222. 1897.

Flowers reflexed at maturity due to bending of the pedicels, usually ochroleucous, 10-1) mm. long; plants usually more robust, up to }; dm. high, and usually less pubescent.

Mountain meadows and stream banks in the Transition and Canadian

20

zones. The only Nevada collection seen came from 7500 ft. in the Burnt Timber Mts., Pole Creek, N Elko Co., Nelson & Macbride 2062 (RM). Mon-

tana to Washington, and southward to Colorado and Arizona.

9. TRIFOLIUM MONANTHUM A. Gray, Proc. Am. Acad. 62523. 1865. (Map 17)

Low, glabrous to villous, mat-forming perennial with eters up to 3 dm. long from a taproot. Leaves 3-foliolate, the leaflets obcordate, obovate, or oblanceolate, rounded, truncate, or retuse at the apex, 2-5 mm. wide, -12 mm. long, sharply denticulate. Peduncles shorter than the leaves. Heads 1-2 (-8) -flowered, with a small involucre of 2-) narrow lobes 0.5-5 mm. long, the flowers erect, or sometimes the peduncle bent below the involucre and the flowers then at more or less right angles to the peduncle. Calyx-teeth narrowly lanceolate, about the same length as the tube. Corolla ochroleucous, with a purple-tiped keel, 10-12 mm. long.

A variable species of Nevada and California. Martin (Madrono 8:230- 233. 196) has delimited four varieties, the following two being found

in Nevada

var. MONANTHUM Trifolium monanthum f. spatiosum McDermott, N. Am. Sp. Trifol. 98. 1910. This is the common form in Nevada, characterized by being glabrous to sparsely villous, the involucral lobes mostly more than 2 mm. long, and the flowers erect. Moist places in the mountains, 6000-10,000 ft., Transition to Can- adian zone. Scattered over most of the higher mountains of Nevada and

extending into the Sierra Nevada and South Coast Ranges of California.

27

var. PARVUM (Kellogg) McDermott, N. Am. Sp. Trifol. 105. 1910.

Trifolium pauciflorum var. parvum Kellogg, Proc. Calif. Acad. Sci. 525). 1873; T. multicaule Jones, Bull. Torr. Club 9:31. 1882; T. parvum Heller, Muhlenbergia 1:11). 1905; T. monanthum var. parvum f. glabrifolium Mc- Dermott, N. Am. Sp.