456 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1955 



To give some idea of the magnitude of their experiments, it might 

 be mentioned that the Central Agricultural Experiment Station at 

 Yangambi has an area of 50,000 acres of tropical high forests where 

 such experiments can be and are being carried out. In the Congo, it 

 is particularly important to try to rationalize kaingining because of 

 the severe transportation limitations on the importation of fertilizers. 

 In central Africa it is out of the question to obtain fertilizers at prices 

 that peasants can pay. Transportation of products out and of ferti- 

 lizer in are both difficult and expensive. Africa does not have good 

 waterways permitting oceangoing vessels access to the interior. Lim- 

 ited and expensive railway facilities must be used. Moreover, these 

 involve repeated transshipment of freight. 



In the Belgian Congo studies of the factors of plant gTowth mider 

 humid tropical conditions are being made. One of the things discov- 

 ered is that it makes a big difference what kind of crops were last 

 raised on the soil before the abandonment of the kaingin. It is also 

 important to keep the soil as continuously covered with crop vegeta- 

 tion as possible to prevent loss of plant nutrients and other types of 

 soil deterioration. 



Belgian agronomists have been devoting much time and effort in 

 an endeavor to rationalize the kamgin or shifting cultivation system 

 of utilizing the tropical high forest and the secondary growth through- 

 out a rotation lasting 15 or 20 years. This is called the corridor sys- 

 tem because the separate but parallel plots of forest for each family 

 are usually 100 meters wide and perhaps a mile long. To direct the 

 peasant farmers most effectively, careful adherence to a regular rota- 

 tion is insisted upon. In 1949 I visited one such colony in the equa- 

 torial forest of the Bambesa district in which over 19,000 peasant 

 families had been settled according to such a plan. Kellogg and 

 Davol 2" have described and figured the corridor system and the re- 

 sults obtained. 



In the "educative" agi'iculture which has been worked out for the 

 Congo peasants, production in quick succession of upland rice and 

 com is followed, where the climate is appropriate, by peanuts, cotton, 

 then manioc (cassava), the main food crop, with which bananas are 

 important as a secondary food crop. After the cassava is dug, the 

 banana plants remain. Natural regeneration of forest trees occurs 

 particularly well in the microclimate mider the abandoned banana 

 plants. Recently Kellogg has published a description of a newer 

 form." 



*• Charles E. Kellogg and Fidelia D. Davol, An exploratory study of soil groups 

 in the Belgian Congo, Publ. Inst, Nat. Etude Agron. Congo Beige, sci. ser., No. 46, 

 p. 66 ff., 1949. 



'^ Charles E. Kellogg, The Fifth International Congress of Soil Science, Leo- 

 poldville, Belgian Congo, August 1954, Proc. Soil Sci. Amer., p. 117, April 1955. 



