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A TEXT-BOOK OF BOTANY 



196. Swamp thickets. A growth of shrubs or low 

 trees may invade the sedgy swamp, giving rise to a thicket. 



FIG. 304. A reed swamp. After KEENER. 



These shrubs and trees are of very uniform type, being 

 mainly willows, alders, birches, etc. 



This series of associations, from pondweed associations 



