14 PRELIMINARY MEASUREMENTS 



1. The last decade measurement should equal one-half the D.I.B. 



as previously tallied. 



2. The age at any cut should be equal to the total number of 



decades minus one, times 10, plus the number of rings recorded 

 in the upper left-hand corner of the space allotted to the first 

 decade measurement. 



3. The consecutive cross-sections should show a decrease in age 



from stump to tip. 



4. Before leaving the tree he should carefully check over the entire 



tally sheet to see that none of the necessary measurements 



have been omitted, 

 (c) In making the necessary calculations he determbies the D.O.B. 

 at each cut instead of the D.I.B. as was done in Problem 6. 

 This is done by adding twice the thickness of the bark to the 

 recorded D.I.B. 



E. References. — Numbers 7, 9 and 80. 



