SHADE TREES. 



223 



FIG. 95. - Showing cross-section of Carolina poplar ( Populus deltoide^ Marsh) . 1, Cross- 

 section of normal stem, enlarged; 2, same, showing abnormal- growth; 3, naked-eye 

 view of same; 4, section of a normal stem; 5, cross-section of trunk of tree showing 

 the splitting of the bark; a, bark; 6, cork cambium; c, cortex; d, phloem; e, abnor- 

 mal parenchyma; /, cambium; g, wood or xylem. 



