188 



wild plants, but 

 on satisfactorily 



Fig. 125.— The 

 avocado is a pear- 

 shaped fruit which 

 botanically is a 

 one-seeded berry. 



PLANTS AND MAN 



in the last fifty years cultivation has been carried 

 in Massachusetts, New Jersey, Wisconsin and 

 Washington. Natural bog lands are used, 

 flooded every winter and spring, and treated 

 with an additional sand covering each season. 

 In the Laurel Family there is the bay tree 

 genus, common to our southeastern states. 

 One species, native to Mexico and Central 

 America, is the avocado. This tree is culti- 

 vated in Florida and California for its green 

 pear-shaped fruit which is a large one-seeded 

 berry (fig. 125). The buttery pulp which 

 surrounds the seed has a high fat content and 

 more proteins than any other fruit; it is used 

 chiefly as a salad plant. It was cultivated by 

 the Aztecs, whose original name for it (agua- 

 cate) has been corrupted into avocado. 



I 



Small Fruits of the Rose Family 



Many of the so-called "berries" are not berries in the 

 botanical sense, but rather various types of accessory or aggregate 

 fruits. Some of these are typical of plants in the Rose Family. The 

 STRAWBERRY is a low-growiug plant which spreads in all direc- 

 tions by means of prostrate stems or runners. The pistils of the 

 flower are seated on a conical receptacle, which after fertiliza- 

 tion enlarges to form the reddish and edible portion of the straw- 

 berry, which is therefore an accessory fruit (fig. 126). The ovaries 

 of the various pistils develop into small achenes scattered over the 

 surface of the strawberry and mistaken for seeds. Strawberries 

 occur throughout temperate regions in both the Old World and 

 the New; they were known as a wild fruit to the Romans, later 

 cultivated during the Middle Ages in France and England. 

 Strawberries are the only small fruit which approaches the impor- 

 tance of the orchard fruits, ranking forth in commercial value — 

 preceded by the apple, peach and grape. The majority of the 

 cultivated American varieties come from the western sand straw- 

 berry, native to our western coasts as well as to Mexico and Chili. 



I 



