iQisl 



BROWN— PINUS STROBUS 



217 



subject are available. For the third the reader is referred to the 

 pubUcations of Wieler (37-39), Jost (13-15), R. and T. Hartig 

 (9-12), MiscHKE (24), and others. 



The amount of seasonal growth in an individual or of growth 

 up to a given point in the season is equal to the sum of the products 

 of the different prevailing growth intensities by the time each was 

 in operation. It follows that these summations would be quite 

 different in different parts of the tree. The only reliable method 

 to indicate the amount of seasonal growth at a given point and at 

 a given time is as a percentage of the previous year's ring. Even 

 this is open to criticism, in that the annual increment often varies 

 between wide limits from year to year. Yet general deductions may 

 be drawn from data of this kind which will indicate to some extent 

 at least the amount of growth at definite times. Table H was made 

 with this idea in view. The figures were obtained from tree I. 

 The width of the previous year's ring represents the average of the 

 last formed rings as exhibited in the 6 different cuttings." 



TABLE H 

 Amount as growth in percentage or previous year's ring, tree i 



On April 26 the greatest proportion of new growth occurred 

 in cutting III, with cuttings I, II, and IV following in the order 

 named. On May 12 the order remained the same except that 

 cuttings I and II had interchanged. On June i5 the ring was, 

 theoretically at least, from one-fourth to over one-half complete; 

 on July 3 from one-third to over two- thirds complete; while on 

 August 13 seasonal growth was over four-fifths complete in all 

 cases." After the last named date, the growth was very sluggish 



"> The last acts as a control and tends to eliminate error. 

 " Growth ceased in cutting I after July 3, 1913; see table F. 



