The University of California’s Ibero Americana monograph series has been consistently producing competent and scholarly historical studies of the settlement geography, demography, and ecology of Latin America, and this latest publication is no exception.
Professor Johannessen’s work on the savannas of interior Honduras is a contribution to what might be called “cultural plant geography”—the study of man’s effects on vegetation. It is generally acknowledged that much of what we consider to be natural vegetation has actually been greatly modified by human actions. There have been, however, few close examinations of the nature of such modifications and how and when they have taken place. Information is lacking in particular for the humid tropics where man’s influence on vegetation is often thought to be negligible and ephemeral.
Based on historical research, field work, and interviews with Hondurans about vegetation changes within their lifetimes, Johannessen concludes that mainly because of overgrazing substantial portions of the grassy savannas of the large valleys of interior Honduras have been invaded by brush and thorn scrub since the early 19th century. This overgrazing, which is still going on, greatly reduces the grass cover and thereby prevents the occurrence of intense ground fires, which are “the most effective weapon against the competitors of grass—the trees.” If woody vegetation will grow on the savannas when burning becomes less intense, then strong support is given to the claim that the grassy valleys encountered by the Spaniards were probably once forested but were maintained in open savanna by hot ground fires ignited by Indians.
The scrub invasion of tropical grasslands to the detriment of grazing potential is not unique to Honduras, but is also presently occurring in the large savannas of Venezuela, Bolivia, Brazil, and locally elsewhere in Latin America. The causes may or may not be the same as those in Honduras. In any event, we now have a solid basis of departure for future studies of the dynamic, changing nature of tropical savannas as result of man’s burning techniques and grazing practices.
This study is of value not only for the theme pursued but also for its informative chapters on the physical geography and the history of human settlement, population, and cattle raising in a country about which relatively little has been written. The historical aspects of the study are carefully documented and evidence a painstaking search of the scattered literature for clues to man’s land-use activities and associated changes in vegetation in Honduras since the 16th century.
