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CINCHONA. 
( Cinchona spp.). 
Cinchona is obtained from the bark of several 
species of Cinchona, which are medium sized trees,. 
25 to 40 ft. high, indigenous to South America. 
The two species most commonly cultivated are 
Cinchona Ledgeriana (Ledger’s bark) and C. 
succirubra (Red bark). The former is much richer 
in quinine than the latter, and is the species chiefly 
grown in Java, which is now the biggest quinine 
producing country in the world. 
Cinchona thrives best at an elevation of 2,000 to 
5,000 ft. and requires a rich loamy soil, preferably 
of volcanic origin. 
The plant is propagated from seed, which is sown 
in specially prepared seed beds, the seedlings being 
transplanted later to distances of about 3 to 4 ft. 
■apart. Where virgin land is available, it is generally 
planted with Ledgeriana seedlings, but land on 
which this variety has been cultivated previously is 
usually replanted with grafted stocks of Succirubra - 
Ledgeriana, that is Ledgeriana grafts on Succirubra. 
FROM the third or fourth year after planting, crop- 
ping by selective thinning and pruning is carried 
out throughout the year, and is continued for a 
period of 15 to 25 years according to the nature of 
the soil. The percentage of quinine in the bark is 
at its maximum about the eighth year after planting. 
When ready for cropping, the trees are lifted with 
the roots intact, since both the root and stem bark 
are rich in alkaloids. The bark is removed and 
dried in artificially heated drying rooms at a tem- 
perature of about 80° C., the resulting product being 
used for the manufacture of quinine. 
