CHAPTER V. 

 CULTIVATION OF MEDICINAL PLANTS. 



There is a growing scarcity of many of the native medicinal 

 plants in the United States, due both to the destruction of the 

 woodlands where they grow and to the direct extermination of the 

 plants themselves by drug collectors, and it seems not improbable 

 that if the collecting of vegetable drugs continues at the present 

 rate it will not be many years before a number of the most impor- 

 tant drug-yielding plants will be exterminated, unless some meas- 

 ures are taken to conserve them in their native localities or to prop- 

 agate them by cultivation. There seems, however, to be little chance 

 for their conservation unless by cultivation, for already the 

 demand is far greater than the supply and in some cases the 

 drugs are scarcely to be had at all. Of the important medicinal 

 plants which are becoming markedly limited in their area of 

 growth may be mentioned those yielding the drugs serpentaria, 

 senega, cypripedium, hydrastis, spigelia and cascara sagrada. 



Not only is there a necessity for the cultivation of medicinal 

 plants on account of the scarcity of the drugs yielded by them, 

 but experiment has shown that in some instances the drug has 

 been improved by giving attention to cultural conditions. The 

 possibilities of what can be done in this direction are shown in 

 the case of coca and cinchona, where by selection and cultivation 

 the plants have not only been conserved but the yield of the 

 medicinal products has been greatly increased. It is true also 

 that very many of our economic plants have been improved by 

 selection and cultivation, as corn, wheat, potatoes, fruits of 

 various kinds, and there is reason to believe that like results 

 would follow the cultivation of medicinal plants. The fact should 

 not, however, be overlooked that in some instances the wild plants, 

 as those of the solanaceous-drug group, are said to give a better 

 yield of the active principles than the cultivated ones ; but this 

 would probably not result if the nature of the plants were better 

 understood and the methods of cultivation improved accordingly. 



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