8 VEGETATION IN CENTRAL AMERICA. 



we can form a definite idea of the original conditions we can not 

 expect to judge of their influence on primitive man, nor can we 

 determine what effects man has had upon the vegetation and other 

 natural conditions. We need what might be called a bionomic base 

 line, an idea of the conditions which existed before man came upon 

 the scene, the conditions which would again supervene if the human 

 inhabitants were withdrawn. 



To invoke other than the human agencies to account for the present 

 lack of forests in many parts of Central America is superfluous, for 

 the destructive abilities of the Indians are everywhere in evidence. 

 Reforestation is everywhere going on, but the Indians are also busy 

 cutting down and burning the woody vegetation. If the burning over 

 of the land were limited to areas ready for planting the general re- 

 sults would be far less disastrous, but the fires are usually allowed to 

 spread wherever there is fuel to carry them, and large tracts of land 

 are thus kept in a permanently barren condition. At night in the 

 farm-clearing season the burning mountain slopes gleam with lines of 

 light like the streets of distant cities. By day the sky is darkened 

 and the air is heavy with smoke. That regions now so barren as the 

 vallejr of Salama in central Guatemala may be artificial deserts 

 cleared by human agency can readily be understood when the facts 

 are viewed at first hand. The devastation which can be worked in a 

 single corn-planting season will go far to convince the careful ob- 

 server that the native methods of agriculture have wide-reaching 

 effects. 



The Central American Indians are extremely conservative people. 

 Even those who have learned to speak Spanish and to wear European 

 clothes still continue to follow their own primitive systems of agri- 

 culture without any appreciable change. With the exception of a 

 limited use of wheat and of broad beans at very high elevations, no 

 European field crops have been adopted by the Indians, much less any 

 European methods of cultivation. Thus the present conditions may 

 be relied upon as giving us a correct idea of the agricultural influ- 

 ences which have long been at work in these countries. 



DIVERSE SYSTEMS OF MAIZE CULTURE. 



The problem of tracing relations between agriculture and natural 

 conditions in Central America is much simplified by the fact that one 

 staple crop is grown over the whole area, including the humid trop- 

 ical lowlands, the dry interior table-lands, and the cold, cloud- 

 covered mountain slopes of high elevation. In spite of endless local 

 diversities among the native inhabitants they have a general agri- 

 cultural unity, for they all depend on Indian corn, sometimes to the 

 almost complete exclusion of other kinds of food. 



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