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TEXTBOOK OF BOTANY 



Fig. 202. Basswood bark industries of eastern woodland Indians. Photo from 

 American Museum of Natural History. 



No civilization of any note was possible prior to the development of a 

 primitive agriculture. Among the more valuable accomplishments of pre- 

 historic man we must include his discovery of the methods of plant 

 propagation. With this knowledge the tribes were no longer forced to live 

 as nomads and raid other tribes when the local supply of wild plants and 

 animals became depleted. They could establish stable abodes in moist 

 fertile areas, and through a division of labor obtain food sufficient not 

 only for those engaged in agriculture but also for other members of 

 the community otherwise employed. 



Following the discovery of methods of plant propagation, primitive 

 man, by transporting and planting seeds and vegetative propagules, 

 could permanently occupy new areas. Without this knowledge the early 

 civilization that developed in the Nile Valley would have been impos- 

 sible, for Egyptian agriculture was accomplished with plants introduced 

 from Eurasia. In the United States today we are largely dependent upon 

 plants that were first domesticated in other parts of the world. The most 

 outstanding exceptions are our forest trees. 



The evolution of cultivated plants has gradually progressed since pre- 

 historic times to the present. Today this progress is accelerated by a more 



