THE CORRECTION AND COMPARISON OF CURVES OF GROWTH. 



131 



of the curve, but leave the later parts untouched. This gives the final curve indicated 

 in the solid line. In this the sinuosities still occur at the same places as in the original 

 upper curve, but are more distinct than there. Taken as a whole the finally corrected curve 

 does not trend markedly either up or down, though the portion included in the seventeenth 

 century is on the whole somewhat higher than that of the two later centuries. 



UTSRQPONMLKJ IHGPEDCBA^A^ =Group 



100 120 140 160 1«0 200 220 240 26U 280 300 310=Age of trees at cutting 



16 12 14 37 48 62 58 33 40 29 26 38 30 29 36 26 20 17 16 16 9 6 = No of trees 



UTSRQPONMLKJ IHGFEDCB A^A-A' = Group 



Fig. 30.— Variation in Radial Growth by Decades, Illustrating the Correction for Longevity of 



the Yellow Pine in New Mexico. 

 Vertical scale: one small square equals 0.20 inch. 



Let us next examine the other curves derived from data furnished by the United States 

 Forest Service. With these I have included the last 300 years of the curve of the Sequoia 

 washingloniana based on nearly 200 trees measured in 1911. This may here be treated 

 in the same way as the others, although in the next chapter we shall consider the entire 



