308 FOUNDATIONS OF BOTANY 



be, of a hundred other kinds, the seed-plants not all in 

 bloom at any one season, but coming along in succession 

 from earliest spring until the approach of winter. The 

 entire set of plants which naturally occupies a given area 

 of land under somewhat uniform conditions is called a 

 plant society. 



379. Similar Societies due to Similar Conditions. — As 

 soon as the young botanist begins to collect plants in a set 

 of localities new to him, he discovers that his old acquaint- 

 ances are still to be found grouped as he has been accus- 

 tomed to see them. The rich black loam of a wooded 

 bank a hundred miles away from his familiar collecting 

 ground will show the same assemblage of slippery elms 

 and lindens, red buds, bladdernuts, and wahoos, hepaticas, 

 bloodroots, Dutchman's breeches, trilliums, pepper root, and 

 wild ginger, with a multitude of later-blooming herba- 

 ceous plants, that he has learned to know so well. The 

 muddy borders of ponds from Maine to Minnesota and 

 beyond are fringed with the same kinds of bur-reeds and 

 sedges, set with water-plantain, and decorated with the 

 soft white blossoms of the arrowhead. The sand dunes 

 along the northern Atlantic coast and those that border 

 Lake Michigan are clothed with a sparse vegetation which 

 in both cases includes the little beach plum, such coarse 

 grasses as that shown in Plate I, and the straggling sea 

 rocket. Barnyards and waste grounds about farm build- 

 ings from Massachusetts to Missouri contain such weeds 

 as the dog fennel, the low mallow ("cheeses"), mother- 

 wort, catnip, and some smartweeds. 



A little study of such cases soon leads one to the con- 

 clusion that these plant societies and multitudes of others 



