GENERAL METHODS 



133 



face of the concrete. If the drainage is poor, if 

 there are many openings, if the tree twists and 

 bends in the wind, use asphalt. These rules gov- 

 ern fillings only. In a succeeding chapter will be 

 found accounts of cavity treatments which do not 



The two trees at the left are proper subjects for cement fill- 

 ings. Those at the right must be filled with asphalt or 

 treated by the open system, without fillings 



involve filling, and also discussions of the value 

 and proper use of each. 



Coming ;iow to the actual operations of putting 

 in the filling, the methods of handling concrete 

 will be described first — then the use of asphalt. 



FILLING WITH CONCRETE 



Concrete fillings can be put into trees in a num- 

 ber of different ways. And the differences, though 



