CULTURE. 



13 



the inoculation of the plant with disease germs. A number of the 

 upright-growing species of Cereus have been used successfully for 

 stocks, and there seems to be no limit to the number of species 

 that may be used. It has been found, however, that some are. 

 better than others for the purpose. When it is desired to have 

 the scion a foot or more high, good stocks may be obtained from 

 Cereus stellatus, C. serpentinus, and other species of similar habits 

 of growth. These stocks are preferable for use in grafting Cereus 

 jlagelliformis and species of Epiphyllum and Rhipsalis, which nor- 

 mally grow in a pendent position. Where only short stocks are 

 desired the above may be used, and also Cereus nycticalus, C. tor- 

 tuosus, C. bomplandii, C. macdonaldiae, and C. grandijiorus. These 

 latter plants are weak stemmed when allowed to grow tall; hence, 

 they can not be used for high grafts unless supported by a stake of 

 some kind. All these species are readily grown from cuttings, 

 which should be somewhat longer than the stock is to be. When 

 the cutting is thoroughly rooted it should be potted and kept in 

 good growing condition until a new root system has formed. It will 

 then be ready to receive the scion after having been cut back to the 

 desired height. 



CULTURE. 



Cacti thrive from southern Canada to far down in South America. 

 Between these extreme points there is scarcely any combination of 

 atmospheric and soil conditions that does not support one or more 

 species of the family. They are found near the seashore in the 

 Tropics, as well as high up on the mountains, where in winter they 

 are subjected to severe frosts. They are most abundant, however, 

 in the higher serniarid tablelands. With these facts in mind, it is 

 clear that when collected they can not all be treated alike, but must 

 be grouped according to the conditions under which the individuals 

 grow in their native haunts, and each group must receive a different 

 treatment to accord therewith. 



Epiphyllum, Rhipsalis, a few species of Phyllocactus, and some 

 species of Cereus are epiphytic in their tropical homes and should be 

 given like treatment in conservatories. They should be grown under 

 practically the same warm, moist atmospheric conditions as are 

 tropical orchids, which may be grown in baskets of peat and moss, 

 or be trained on blocks or stumps, or on walls, wherever the roots 

 have opportunity to penetrate a moisture-laden medium. Most 

 species of Phyllocactus and of the climbing species of Cereus should 

 be grown in orchidlike conditions of temperature and humidity but 

 in very loose, moderately rich soil. For this purpose a mixture of 

 loam, sand, and an abundance of thoroughly decomposed leaf mold 

 makes an excellent soil. By far the greater number of species of 



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