10 



FIRST BOOK OF FORESTRY 



Here is another smooth spot on a rough-barked tree. 

 This is evidently not of the same kind as the one we have 

 already noticed. Why, there are two, on opposite sides of 



the tree ; and note there 

 are similar spots on yon- 

 der elm ! Sighting along 

 we see more of them on 

 other trees, and always 

 _ B two on each tree. They 

 are the blazes of survey- 

 ors or of some one who 

 wished to mark a line. 

 Were we to cut through 

 one of these blazes, as 

 along the line AB, Fig. 

 6, a, it would probably 

 have the appearance 

 shown in Fig. 8, 6. 



Counting the rings we 

 would find that the blaze 

 was made when the 

 twentieth ring had been 

 formed, and since there 

 are now thirty-two rings on this section, it means that the 

 blazes were cut twelve years ago. Three successive stages 

 representing the fresh blaze, the same seven years ago, 

 and as it now appears are shown in Figs. 6 to 8. 



Outer 

 Bark 



FIG. 



"-Bast 



The " Blaze " as it appeared 



when first made 

 a, front view ; b, cross section on line AB 



