KEY TO THE GENERA OF LEGUMINOSAE 

 REACHING TREE SIZE 



1. Leaves bi-pinnately compound (3-4-pinnate in some genera and 

 sometimes only pinnate in Gleditsia) ; flowers regular or nearly so, 

 2. Flowers in globose heads or cylindrical spikes; leaflets mostly less 

 than Yi inch long; southwestern shrubs seldom becoming trees. 

 3. Twigs armed with spines; filaments free; legume terete or com- 

 pressed, indehiscent. 

 4. Flowers in heads or spikes, yellow or white, stamens more 



than 10; petioles not spiny or glandular at apex 



Acacia Mill., Acacia, p. 269. 



4. Flowers in cylindric spikes, greenish-white, stamens 10; 

 petioles minutely glandular at apex and tipped with small 

 spinescent rachis Prosopis L., Mesquite, p. 271. 



3. Twigs unarmed; legume compressed, dehiscent; flowers in 

 heads, whitish, or pink. 



5. Stamens numerous, long-exserted ; flowers pink; planted 

 in southeast Albizia Dur., Mimosa, p. 271. 



5. Stamens 10-20; flowers white; western. 



6. Stamens 12-20, exserted, their filaments imited into a 



tube; legume broad. Lysiloma Benth., Lysiloma, p. 266. 



6. Stamens 10, inserted, their filaments free; legume linear. 



Leucaena Benth., Leadtree, p. 266. 



2. Flowers in racemes; stamens 10 or less, their filaments free. 



7. Flowers large and showy, yellow, perfect; leaflets less than H 

 inch long; southwestern shrubs or rarely small trees. 

 8. Stamens red and long-exserted; legume broad and flat; 



naturalized Poinciana L., Poinciana, p. 266. 



8. Stamens inserted; native. 



9. Legume linear, terete; rachis of leaf spinescent 



Parkinsonia L., Parkinsonia, p. 279. 



9. Legume oblong, compressed; rachis of leaf not spinescent 



Cercidium Tulasne, Paloverde, p. 279. 



7. Flowers not showy, greenish-white, polygamous or dioecious; 

 leaflets over 3^ inch long; eastern trees, but widely planted. 

 10. Leaves 1-3 feet long with leaflets 2-2 14 inches long; legume 



thick and woody with seeds % inch long 



Gymnocladus Lam., Cofifeetree, p. 275. 



10. Leaves H-1 foot long with leaflets H-1 H inches long; 



legume leathery with seeds H inch long 



Gleditsia L., Honeylocust, p. 277. 



1. Leaves simple or pinnately compound; flowers papilionaceous. 

 11. Leaves simple. 



12. Leaves heart-shaped; flowers in fascicles, red, with free 

 stamens; spineless Cercis L., Redbud, p. 273. 



12. Leaves oblong or absent; flowers in racemes, blue, stamens 

 with 9 united anthers; twigs reduced to spines; Arizona and 

 California Dalea Juss., Dalea, p. 266. 



11. Leaves pinnately compound. 



13. Leaflets 1-4 inches long. 



14. Leaves 3-foliate; flowers red 



Erythrina L., Coralbean, p. 266. 



14. Leaves many-foliate; flowers white, yellow, or blue. 



15. Leaflets 3-4 inches long; flowers white, in panicles; 



legume compressed 



Cladrastis Raf., Yellowwood, p. 275. 



15. Leaflets 1-2 3^ inches long. 



16. Twigs with stipular spines; legumes compressed, 



not constricted Robinia L., Locust, p. 283. 



16. Twigs unarmed; legumes terete, constricted. . . . 



Sophora L., Sophora, p. 281. 



13. Leaflets less than 1 inch long. 



17. Leaves with glandular dots 



Eysenhardtia H. B. K., Kidneywood, p. 266. 



17. Leaves without glandular dots. 



18. Flowers fascicled, yellow 



Caragana Lam., Pea Tree, p. 281. 



18. Flowers racemose, purple 



Olneya Gray, Tesota, p. 266. 



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