GENUS 23. 



PEA FAMILY. 



i. Robinia Pseudo-Acacia L. Locust-tree. 

 False or Bastard Acacia. Fig. 2526. 



Robinia Pseudo- Acacia L. Sp. PI. 722. 1753. 

 Pseudo-Acacia odorata Moench. Meth. 145. 1789. 



A large tree with very rough bark, maximum 

 height of about 80 and trunk diameter of 35, rarely 

 shrubby. Twigs and foliage nearly glabrous; stip- 

 ules often spiny; leaflets 9-19, stalked, ovate or oval, 

 mainly rounded at the base, obtuse or emarginate 

 and mucronulate at the apex, entire, i'-z' long ; 

 stipels small, setaceous ; racemes loose, drooping ; 

 pedicels slender, 3"-6" long; flowers white, fra- 

 grant, 7"-io" long, the standard yellowish at base ; 

 pod glabrous, 2' -4' long, about 6' wide, 4-7-seeded. 



Monroe Co., Pa., south, especially along the western 

 slopes of the mountains, to Georgia, west to Iowa, Mis- 

 souri and Oklahoma. Extensively naturalized else- 

 where in the United States and eastern Canada and in 

 Europe. Wood strong, very durable, greenish brown, 

 the sap-wood yellow ; weight per cubic foot 46 Ibs. 

 Much used for posts, in ship-building, and especially 

 for tree-nails. Called also white, yellow, black, red- 

 flowering or green locust. Honey-, pea-flower or post- 

 locust. Silver-chain. May-June. 



2. Robinia viscosa Vent. Clammy or 

 Honey Locust. Rose Acacia. Fig. 2527. 



Robinia viscosa Vent. Hort. Cels, pi. 4. 1800. 



A small tree, with rough bark, maximum 

 height about 40 and trunk diameter 10'. Twigs 

 and petioles glandular-pubescent, viscid ; stip- 

 ules short, sometimes spiny; leaflets 11-25, 

 stalked, obtuse, and mucronate at the apex, 

 mostly rounded at the base, ovate or oval, 

 I '-2' long, thicker than those of the preceding 

 species; stipels small, subulate ; racemes rather 

 dense, often erect ; pedicels 2" -4" long ; flow- 

 ers pinkish, p"-i2" long, not fragrant; pod 

 2'-4' long, about 6" wide, glandular-hispid. 



Mountains of Virginia to Georgia. Escaped 

 in the Middle States and north to Nova Scotia. 

 Wood brown, the sap-wood yellow ; weight per 

 cubic foot 50 Ibs. Rose-flowering or red-locust. 

 June. 



3. Robinia hispida L. Rose Acacia. . 

 Bristly or Moss Locust. Fig. 2528. 



Robinia hispida L. Mant. 101. 1767. 



A much-branched shrub, 3-9 high. Twigs, 

 petioles, pedicels and rachises of the leaves 

 bristly; stipules very small, or none; leaflets 

 9-13, stalked, broadly ovate or oblong, entire, 

 mainly obtuse or rounded at each end, mu- 

 cronate, i '-2' long; stipels none or subulate; 

 racemes loose ; pedicels 3"-6" long ; flowers 

 pink or purple, 8"-is" long, not fragrant; pods 

 linear, bristly-hispid. 



Mountains of Virginia to eastern Tennessee and 

 Georgia. Often cultivated for ornament. Honey 

 locust. May-June. 



