TAPPING MARITIME PINES. 



715 



(5 to 6 inches) distant from the former, or on the other 

 side of the tree exactly opposite to it. Thus, in time, 

 grooves are made all round a tree, and then fresh ones are 

 made between them. By this procedure, resin is extracted 



3S2. Cross-section of a pine which has been tapped "alive repeatedly." 



1. Groove cat when li> years oM. 



2- 22 " 



3- 27 



4. 31 8. 



The last grove still in use. 



5. Groove cut when 34 years old. 



6. 38 



7. 42 



whilst the pines are kept alive for a long period (Figs. 382, 

 383). 



When, owing to a tree being exceptionally vigorous, or to bad 

 treatment, two grooves are made at the same time, which* is 

 generally the case in private forests, they should be worked 

 simultaneously at different heights. 



