LATHYRUS 



LATHYRUS 



1825 



S. Amer. Orobus niger and 0. vernus are common garden 

 names, but Bentham & Hooker, also Engler & Prantl, 

 make Orobus a subgenus of Lathyrus, characterized in 

 part by the lack of tendrils. See Orobus. 



The genus is best known by the sweet pea. Most 

 other forms are perennial, although some of these are 

 cultivated as annuals. All are free -growing plants, 

 so independent in their ways that they require a place 

 to grow by themselves, apart 

 from other plants of like habit 

 or size. Hence they are to be 

 grown alone, on trellises or 

 against walls, in rock-gardens, 

 or allowed to form a wild tangle 

 among strong shrubs. The 

 chief value of the annuals is for 



cut -flowers, although 

 their part in the garden 

 is not to be ignored. 

 As a temporary screen 

 in summer for shut- 

 ting out unsightly ob- 

 jects, they are valuable, 

 or for quickly covering 

 trellises or rough places 

 otherwise unsightly. 



The perennials are 

 of comparatively easy 

 cultivation, succeeding 

 in any garden soil. The annuals are more exacting in 

 their requirements, demanding a moderately rich gar- 

 den soil, abundant moisture, coolness and depth for 

 their roots, and open sunlight. All are grown from seed, 

 sown very early in the open to secure the required cool- 

 ness for the roots. The perennials are propagated, in 

 addition, by division, special varieties being increased by 

 cuttings in the fall, after the flowering season, or in spring 

 from old plants stored in the greenhouse. The roots 

 of perennials are long and fleshy, and, when once estab- 

 lished, usually continue for years without attention. 



2111. Lathyrus tingitanus. Some- 

 times sold as a form of sweet pea. 

 (XH) 



albiflorus, 7. 

 albus, 7, 8, 19; suppl. 

 flaccidus, 19. 

 grandiflorus, 3, 7. 

 laetiflorus, 15. 

 latifolius, 7. 

 luteus, 16. 

 magellanicus, 8. 

 magnificus, 7. 

 maritimus, 11. 



116 



INDEX. 

 montanus, 16. 

 myrtifolius, 10. 

 niger, 18. 

 odoratus, 1. 

 ornatus, 20. 

 palustris', 10. 

 polymorphic, 17. 

 pubescens, 9. 

 rotundifolius, 5. 



SMhorpii, 6. 

 splendens, 7, 13. 

 sylvestris, 4. 

 tingitanus, 2. 

 undulatus, 6. 

 venosus, 12. 

 vernus, 19. 

 violaceus, 14. 

 Wagneri, 4. 



A. Habit climbing: Ivs. tendril-bearing. (Lathyrus.) 

 B. Plants annual: Ifts. 1 pair. 



1. odoratus, Linn. SWEET PEA. St. rough-hairy, 

 winged: Ifts., oval or oblong, mucronulate; stipules 

 lanceolate: peduncle 2-4-fld., much longer than the Ivs.; 

 fls. in shades of blue, red, yellow and white, fragrant, 

 the shield large and showy, expanded, sometimes 

 "hooded:" pod 1-2 in. Summer. Italy. B.M. 60. 

 For cult, and varieties, see Sweet Pea. 



2. tingitanus, Linn. TANGIER SCARLET PEA. Fig. 

 2111. Sts. spreading, winged, glabrous, 3 ft. long: Ifts. 

 linear-lanceolate, obtuse, mucronulate; stipules lanceo- 

 late: peduncle 2-fld., longer than the Ivs.; fls. 1 in. long, 

 dark red-purple; shield large, purple, wings and keel 

 bright red: pod 45 in. long. June, July. W. Medi- 

 terranean region. B.M. 100. An earlier annual than 

 the sweet pea, and because of its vigor will run it out. 

 It has been grown for forage. 



BB. Plants perennial. 



c. Lvs. with 1 pair of Ifts. 



D. Stipules narrow. 



3. grandifldrus, Sibth. and Smith. EVERLASTING 

 PEA. TWO-FLOWERED PEA. Fig. 2112. St. winged, 

 4-6 ft. long: Ifts. large, ovate, obtuse, mucronulate, 

 undulate; tendrils branched, short; stipules small: 

 peduncles, 2-3-fld., longer than the Ivs.; shield large, 

 obcordate, notched, broad, rose-purple, wings dark 

 purple: pod linear, 3 in. June, July. S. Eu. B.M. 



1938. Larger vine than L. lati- 

 folius, but weaker and less rampant. 

 Fls. as large as those of the sweet 

 pea. Free-flowering, succeeding in 

 any soil, not requiring much light. 

 Adapted to banks, along path- 

 margins in woods, among strong 

 shrubs, and as a covering for rocks. 

 4. sylvestris, Linn. FLAT PEA. 

 St. straggling or climbing, 3-5 ft. 

 long, stout, winged, glabrous, with 

 creeping rootstock: Ifts. linear- 

 lanceolate, thick, with winged lf.- 

 stalk: peduncle 3-6-fld., equaling the Ivs.; fls. Hin. 

 long; standard rose, with green spot on its back; 

 wings purple at summit; keel greenish: pod lanceo- 

 late, 2-3 in. long. All summer. Eu. Inferior orna- 

 mentally to other perennials; sometimes mentioned 

 (in the domestic var. Wagneri) as a forage plant and 

 for plowing under in a green state as a fertilizer. 

 Grows well on poor, unimproved sandy soil, and is 

 unaffected by frosts and droughts. For garden cult., 

 it may be sown in a seed-bed and transplanted when 

 of suitable size. Its seeds in the wild state are said 

 to be to some degree unhealthful, but in the cult, form 

 this quality has been bred out. 



5. rotundifSlius, Willd. PERSIAN EVERLASTING PEA. 

 Low-growing, winged species: Ifts. ovate; stipules 

 toothed: peduncles many-fld., longer than the Ivs.; 

 fls. large, rose-pink. June. Russia and the East. 

 B.M. 6522. A species of easy cult, requiring a cool, 

 shady and sheltered position. Adapted to stony banks. 



6. undulatus, Boiss. (L. Sibthorpii, Baker). Sts. 

 twining, broadly winged: Ifts. oblong: peduncle 5-6-fld.; 

 fls. a mauve-red. A form intermediate between L. 

 latifolius and L. rotundifolius. A somewhat tender 

 species, said to be 6 weeks earlier than any other. 



DD. Stipules broad. 



7. latifdlius, Linn. EVERLASTING PEA. PERENNIAL 

 PEA. Fig. 2113. St. winged, 4-8 ft.: Ifts. ovate-elliptic 

 or ovate-lanceolate, somewhat glaucous, mucronate, 

 2-3 in. long; tendril branching: peduncle many-fld., 

 longer than the Ivs.; fls. rose, large: pod flat, 4-5 in. 

 long. Aug. Woods of Eu. This is the common peren- 

 nial pea, and one of the hardiest and most easily cult. 



