The Pod-bearers 



CC. Leaves without spiny stipules; flowers white, in 

 loose clusters. 



5. Genus CLADRASTIS, Raf. (C. lutea) yellow-wood 



The family Leguminosae, to which our pod-bearing trees 

 belong, is one of vast size and economic importance, and of 

 world-wide distribution. There are nearly 450 genera and over 

 7,000 species. Peas, beans, lentils, clover — all plants that bear 

 simple, 2-valved pods after the flowers — are included. By this 

 sign they are easily recognisable when in fruit. Besides food 

 stuffs, the pod-bearers yield rubber, balsams, oils, dyestuffs, 

 good timber, and a long list of ornamental plants. The grass 

 family, which includes the chief forage and grazing plants, the 

 grains and sugar cane, is the only one that ranks higher than the 

 legumes in service to the human family. 



The pod-bearers are the only plants that have the power 

 to abstract nitrogen from the air and store it in their stems and 

 roots. The rotting of these parts restores to the soil that particular 

 plant food which is most commonly lacking and the costliest to 

 replace. The cheapest way to put nitrogen into the soil is to 

 plough under green crops of clover, cowpeas, or other legumes. 

 They improve the texture and therefore the moisture-holding 

 capacity of the soil; commercial fertilisers do not. Legumes 

 grow on poor soil and make it rich. 



American pod-bearing trees belong to several different genera, 

 with one or more species in each. With few exceptions they have 

 handsome pinnate foliage, and showy flowers in drooping clusters. 

 These characters, combined with an admirable form, give these 

 trees prominence as ornamentals wherever they will grow. Their 

 pods are often highly decorative in summer and winter. The 

 thorns of certain species give the trees character and distinction. 

 Several valuable lumber trees are included in the family. In 

 North American forests seventeen genera of pod-bearers are 

 native. These include over thirty species. Beside these, several 

 exotic species are met with in cultivation. 



I. Genus CERCIS, Linn. 



The genus Cercis, including seven species of shrubs and trees, 

 is distributed in Asia, Europe and America. We have two tree 

 forms and one shrubby species, native to California. 



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