THE BIOTIC ENVIRONMENT OF ORGANISMS 



581 



Fig. 33.16. The montane cloud forest of Honduras. This climax association develops at 

 elevations of 6,500 to 7,000 feet where the mountain summits rise into the trade wind 

 clouds. The slopes below are occupied by pine forests, and the valleys, by grassland and 

 thorny scrub; but "la montana Uorona" (the weeping forest) of the peaks is always dripping 

 wet from rain or mist. This vapor forest is similar in appearance to the most luxuriant 

 tropical rain forest, though very different in details of composition. Many of its trees are 

 immense; every tree is loaded to capacity with epiphytes, and every exposed bark surface 

 is covered with a wet sponge of filmy ferns, mosses, and leafy liverworts. The tree canopy 

 is continuous; below it are tree ferns, shrubs of the melastome family, and a multitude of 

 other plants. In spite of the lavishness of the plant life, animals are relatively few. This is 

 the home of the quetzal, sacred bird of the Aztecs and Mayas, and of various other inter- 

 esting species; but in abundance and variety of vertebrate and invertebrate life it does not 

 compare with the tropical lowland forests. (Photo taken on Cerro Uyuca, Honduras, by 

 Prof. Archie F. Carr, Jr.) 



had destroyed most of the forests. The time required for the completion 

 of successional changes within a stable climate probably ranges from 

 several hundred to many thousands of years, depending upon the kinds 

 of areas that were originally available to the various types of pioneer 

 communities, the length of the growing season, and the nature and rate 



