GROWTH IN EVEN-AGED STANDS 75 



Part II.— Office Work 



Note.— In order that enough data for the construction of a table may be at hand the 

 field work of the entire class should be collected for the use of each student. (For schools 

 8o situated that it is impracticable to collect appropriate data, Data Series VI has been 

 included in the Appendix.) 



A. Construct a table giving the following information in 10-year periods: 



(a) The average number of trees per acre; 



ib) The dianieter of the average tree; 



(c) The average diameter; 



(d) The average total basal area in acre terms; 



(e) The average height; 



(/) The average volume in cubic feet in acre terms. 

 Note. — All average values should be evened off by curves. 



B. Arrange all data, curves and other work in logical order. 



C. Discussion. 



1. Outline the measurements and office work required as if the object 



were to show only the growth at D.B.H. in 10-year periods. 



2. Compare this method with that of Problem 33 with reference to the 



conditions under which each would be applicable. 



3. Could this method be modified for the determination of growth in 



uneven-aged stands? If so, show how you would modify it. If 

 not, why not? Consider in your reply the difference in the character 

 of the stands, and in the silvicultural conditions of growth, and the 

 method of studying growth in uneven-aged stands. (See Problem 

 27.) 



4. Would the method be applicable to mixed stands? Show how, or, 



if not applicable, wh}^ not? 



5. Which would you consider the more accurate for the determination 



of the average age, the average age of the sample trees or the aver- 

 age age of the dominant trees? Why? 



