8 SHADE IN COFFEE CULTUKE. 



crop, to waste no space but to lose nothing by overcrow ling, to 

 improve quality without diminishing quantity, to obtain timber or 

 other secondary products of value — in the investigation of these and 

 many similar questions of coffee culture the habits and characteristics 

 of the various leguminous trees may furnish factors of the greatest 

 importance, and the study of them will become a regular part of the 

 investigations of tropical agriculture. Not only coffee, but cacao 

 (chocolate) and coca (cocaine) are culturally connected in South Amer- 

 ica with leguminous trees, and even Guinea grass has been said to 

 thrive best under the shade of Pithecolobiuni saman. It has accord- 

 ingly seemed desirable, as a basis for further observation and experi- 

 ment, to bring together some of the recorded information bearing 

 upon the planting of leguminous trees with coffee. 



Although direct historical evidence has not been found, 1 it seems not 

 unreasonable to believe that the use of leguminous trees for shade 

 purposes is a legacy from the prehistoric agriculture of the native 

 races. Both cacao and coca were extensively culth^ated before the 

 advent of Europeans, and early accounts of the culture of the former 

 make reference to recognized use of shade trees. Moreover, it is 

 exactly in the cacao regions that the most uniform use of leguminous 

 trees for shade has appeared. 



THE DIRECT EFFECTS OF SHADE. 



The various ways in which shade may affect the growth of such a 

 plant as coffee may be grouped, for convenience of consideration, as 

 direct and indirect. To maintain that shade is directly beneficial is 

 but a converse of the proposition that sunlight is harmful, since 

 reduced temperature and sustained humidity of the atmosphere and 

 soil, and other similar and attendant results affect the coffee plant 

 only indirectly and have been considered heretofore as merely inci- 

 dental to the shade. 



Although no writer of practical experience has maintained that 

 shade is directly beneficial to coffee, many compiled and semipopular 

 works repeat statements to the effect that dense shade is the "first 

 essential to the life of the coffee bush," and some have taken the 



1 This deficiency has been supplied since the manuscript of the present report was 

 sent to the printer. The following passage is from Acosta's account of cacao: 



"The tree whereon this f ruite growes is of reasonable bignesse, and well fashioned; 

 it is so tender, that to keep it from the burning of the Sunn*. 1 , they plante neere unto 

 it a great tree, which serves only to shade it, and they call it the mother of Cacao. 

 There are plantations where they are grown like to the vines and olive trees of 

 Spaine. The province where there is greatest trade in cacao is Guatimala. There 

 grows none in Peru, but this country yields Coca, respecting which there is another 

 still greater superstition." "The Natural and Moral History of the Indies," 1590. 

 Hakluyt Society edition, 1880, 1 : 245. 



