Zonal Arrangement of Plants 



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Fig. 190. Zonal arrangement of plants. At the front is a zone of Marsilea 

 extending down into the water. Next is a zone of bur-reed, with the 

 spiny seed-heads showing near the center of the picture. Back of this 

 is a zone of tall composites. The flower clusters of the joe-pye-weed 

 show above the bur-reed tops. In the background is a zone of trees. 



