184 IMPORTANT FAMILIES OF PLANTS 



aiso a very ancieut agriculture iu parts of America, but it is 

 very doubtful if it is as old as the eastern agriculture. 



Maukind very naturally began to cultivate those plants which 

 they had previously used from the wild and the practice very 

 naturally tended to discourage their nomadic habits. Increas- 

 ing population very naturally made greater and greater demands 

 on agriculture and resulted in improved methods, the selec- 

 tion of the best plants and the introduction of new plants. 



Westward Movements. — But man could not give up his 

 old nomadic habits quickly. His love for the chase, for travel 

 and exploration, for war and conquest were strong and must bo 

 satisfied by actual experiences. Therefore, we see certain 

 great movements of the human race, such as the migrations of the 

 early Christians from Judea westward, the Crusaders from 

 Europe back to the Holy Land and their return to Europe, the 

 discovery, conquest and settlement of America. These and many 

 other similar movements of greater or less proportions very 

 naturally resulted in the introduction of many new and vahiable 

 plants into countries in which they were previously unknown. 



The history and origin of our agricultural plants is obscure 

 and in some cases the confusion is increased by the names which 

 many of the plants bear. The English walnut is from Persia 

 and not England, the Irish potato is from Peru and Equador 

 and not Ireland, the peach (Prunus persica) is from China, but 

 went into Europe by way of Persia. 



A knowledge of our most important cultivated plants would 

 be well worth while and very interesting. It is of much greater 

 importance than a knowledge of wild flowers, although this line 

 of work should not be neglected. All of our cultivated plants 

 were originally wild plants, and in recent years many of these 

 so-called " wild plants," such as alfalfa and sweet clover, have 

 been brought under cultivation. Useful plants of our own part 

 of the world may be of very little value in other parts. 



