46 



4. In measuring" the girih, the tape should be laid along either 

 the lower or the upper edge of each ring, never along both indif- 

 ferently. Experience has shown that it is most convenient to 

 measure along the lower edge. The tree should be numbered con- 

 secutively for recognition, and the numbers should be painted on 

 the bark close to the ring. Labels, of whatsoever pattern, should 

 never be used, as they ultimately drop off and get lost, and the 

 trees are then no longer recognisable. A careful register of all the 

 measurements taken should be kept in something like the following 

 form : — 



In the last column will be entered all pertinent remarks, such 

 as " Released from lateral pressure in thinnings of 1890 ;" " Over- 

 topped, no longer measured ; " " Found dead in 1896," and so on. 

 If trees of all sizes are represented in the sample plots, a series 

 of from 5 to 15 consecutive measurements, according to the 

 length of the interval at which the measurements are taken (the 

 shorter the interval, the larger the number of measurements re- 

 quired), will furnish complete data for computing the increments 

 for all periods and at various ages. For the jardinage type of 

 forests, each sample plot should contain individuals of various 

 widely-differing ages ; in all other cases, each sample plot should 

 contain only trees belonging to a single age-class, or, if there is a 

 double storey of growth, to two ag6-classes. 



C. Bate of Increase of volume. 



The increment put on during a given number of years n may be 

 obtained in several diiferent ways as follows : — 



I. By the otibing op the stem in sections. — The stem being 

 cut up into sections from 6 to 12 feet long, the actual 



