Medicinal Plants, 



in the course of time gradually become more and more limited in their distribution, 

 adapting themselves to the soil and climatic conditions which prevail in the rather 

 limited areas in which they are now found. They are very rarely found to extend 

 slightly over into the western slopes of the Andes. In their natural haunts 

 climatic conditions seem to influence the growth of cinchonas more than the 

 composition of the soil. They occur, for example, in a great variety of geological 

 formations which seem in no wise to affect their growth or the chemical constituents 

 of the bark. This does not appear to hold good in cultivation, since rich soil, for 

 example, does certainly increase the alkaloidal yield considerably. Above all, 

 cinchonas require good soil drainage ; a checking, clogging or retardation in the 

 soil seepage is very injurious to the growth of cinchonas. While they thrive in 

 regions of heavy and prolonged annual rainfall, it is found that some species and 

 varieties do fully as well or even better in areas of comparatively slight rainfall. 

 They do, however, require considerable atmospheric moisture. 



In their natural haunts the cinchonas are associated with the cocas 

 {Erythroxylon coca) and coffee trees {Caffea arabica) and tree ferns, in sheltered 

 declivities with rich, well-drained soil. There is a Peruvian proverb to the effect 

 that the " cinchonas like to be within sight of snow." A hot climate is fatal, which 

 is no doubt the chief reason why they are not found in the lowlands of the tropics. 

 On the other hand, it is equally evident that a temperature below 27 degrees F, 

 is quite uniformly fatal to the great majority of native species and varieties. 



CLIMATIC CONDITIONS IN CALIFORNIA. 



A brief review of the climatic conditions of California will give some idea of 

 the similarity to the climatic conditions of the natural home of the cinchonas. The 

 coast line of California, nearly 1,000 miles in extent, shows but a difference of 

 10 degrees F. in mean annual temperature. At Eureka (Humboldt county), the 

 temperature is 51 degrees F., at San Francisco, 56 degrees F., and at San Diego, the 

 extreme southern limit, 61 degrees F. At Eureka the mean monthly departure 

 for January is only 5 degrees from the annual mean ; at San Francisco, 6 degrees 

 F., and at San Diego, 7 degrees F. The difference in mean annual temperature 

 between the extreme north and south of California is slight, yet sufficient to modify 

 the character of the vegetation to some degree. The difference in annual rainfall 

 is more marked, with seventy-five or more inches at Eureka, fifty-six inches at 

 San Francisco, and about five or six inches at San Diego. Of special interest to 

 cinchona culture are the records of absolute minimum and maximum temperatures. 

 The records as given in the Climatology of California (1903) show that in San 

 Francisco the temperature has dropped as low as 22 degrees F. (January 28, 1862) ; 

 there are several records of 25 degrees F. (January 20, 1854, and January 31, 1862), 

 and several of 27 degrees and 28 degrees. These records were made by Mr. Thomas 

 Tennent and extended over a period of twenty years (1849 to 1870). To the south 

 of San Francisco along the coast, the temperature increases very gradually and 

 slightly ; to the north it is similarly lowered. At Los Angeles there is an occasional 

 record as low as 28 degrees F. ; at San Diego an occasional drop to 32 degrees F.; 

 at Eureka there are records as low as 20 degrees. F. 



The question of importance, in the light of the previous rather inconclusive 

 experiences and tests and the ascertainable facts regarding climatology, etc. Is it 

 likely that renewed and properly conducted efforts to introduce cinchonas would 

 succeed '? Similitude or similarity of vegetation is not a conclusive guide. For 

 example, the tree ferns do well in San Francisco, but the coffee tree does not survive 

 in the open, and the coca {Erythroxylon coca) has apparently not been attempted, 

 The experiments made by the college of agriculture show quite conclusively that 

 the less hardy species of cinchonas cannot survive the frosts of the middle California 



