OCCUPA TION OF LAND. 303 



ected by man occupy cultivated fields. When cultivation 

 eases, or the crop is removed, or the fields are neglected, 

 mndreds of species of feral plants, which are constantly spring- 

 ig up, now flourish, bear seed, and take more or less complete 



Fig. 254. 

 abandoned field, Alabama, self reforested by pines. (Photograph by Prof. P. H. Mell.) 



ossession of the soil. Impoverished land, abandoned by man, 

 ecomes nurtured by nature. Weeds, grass, flowers spring up 

 1 great variety often. Some can thrive but little better than 

 le abandoned crops, while others, peculiarly fitted because of 

 ne or another adapted structure or habit, flourish. Crab-grass 



