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TEXTBOOK OF BOTANY 



Canebrakes were very extensive in pioneer days, not only near the 

 coast but also far up the slow^-flowing rivers and streams. The cane, 

 Arundinaria, is the only native American bamboo ( Fig. 388 ) . At or just 

 below the soil surface it has extensive branching rootstocks, from which 

 upright leafy poles grow to heights of 10 to 20 feet. These hard, rigid 

 stems, which develop from the numerous nodes of the rootstocks, form 

 almost impenetrable tangles in low ground. Canebrakes are often in- 

 vaded by evergreen "live oaks" on slightly higher land. Live oaks, with 

 their wide-spreading branches hung with the rootless flowering plant 



Fig. 388. A canebrake on the edge of a cypress pond near Baton Rouge, Louisiana. 



"Spanish moss," form an unforgettable feature of the coastal region. 

 Canebrakes also occurred on the bluffs of the Mississippi embayment as 

 far north as Illinois as undergrowth in the beech-magnolia and oak 

 forests. These brakes now have been largely destroyed by burning and 

 by grazing in early spring when the voung shoots appear above ground. 

 A second unique feature of the muddy rivers that cross the coastal 

 plain is the cypress swamps. This deciduous conifer grows in wet, low 

 grounds subject to flooding, and under these conditions upright conical 

 "knees" develop from bends in the shallow roots. When the tree is 

 planted on the upland such outgrowths do not occur. Associated fre- 

 quently with cypress is the tupelo, or black gum, in which the base of 

 the trunk is enlarged when growing in similar situations subject to pro- 

 longed flooding. 



