NO. l8 TREE GROWTH AND RAINFALL— CLOCK 



29 



of tree growth for 4 years out of 32 of variation. Of these opposite 

 trends that for 1910 contains 84 percent of the numerical disagree- 

 ment and, if 1910 be eliminated, the trend coefficient rises to 0.994. 

 A comparison of the rainfall among all seven stations with the tree 

 growth of group 7 for the 4 years of opposite trend, 1910, 1912, 1913, 



Table iS-— Correlation of tree groups mid Chacon rain jail 

 Trend coefficients and ratios of opposed trends 



G 4 G s G 7 Go G 10 G II 



^^^'"•-J^Iy 0-93 0.82 0.96s 0.88 0.06 0.92 



(0.22) (0.31) (0.12) (0.19) (0.16) (0.22) 



Jan.-Aug 0.92 0.73 0.95 0.88 0.94 0.91 



(0.16) (0.31) (0.19) (0.25) (0.22) (0.28) 



Mar.-June 0.85 0.82 0.89 0.77 



(0.28) (0.28) (0.16) (0.28) 



May-Aug 0.80 0.68 0.80 0.66 



(0.25) (0.37) (0.28) (0.28) 



May-June 0.73 0.70 0.72 0.49 



(0.31) (0.34) (0.28) (0.34) 



Tan.-May 0.72 0.32 0.70 0.62 



(0.25) (0.44) (0.28) (0.41) 



Nov.-May 0.71 0.26 0.68 0.59 



(0.23) (0.42) (0.26) (0.39) 



Mar.-Apr 0.50 0.44 0.55 0.52 



(0.41) (0.44) (0.37) (0.50) 



May-July 0.84 0.71 0.85 0.71 



(0.22) (0.31) (0.19) (0.25) 



April 0.04 0.20 0.09 0.14 



(0.47) (0.47) (0.56) (0.56) 



May 0.75 0.34 0.64 0.27 



(0.25) (0.44) (0.34) (0.41) 



June 0.42 0.79 0.59 0.54 



(0.47) (0.25) (0.37) (0.44) 



July 0.62 0.48 0.66 0.63 



(0.41) (0.50) (0.37) (0.37) 



August 0.39 0.33 0.35 0.27 



(0.37) (0.44) (0.41) (0.41) 



and 193 1, shows that from one to three stations disagree with the 

 remainder in each case. The 5 years of greatest parallel variation in 

 the complete record have only one station disagreeing with the re- 

 mainder for I year. Where the parallel variations are of small amount 

 the different rainfall stations are much at variance with each other 

 for all years. Therefore, it is possible to speculate that the rainfall 

 at the site of the trees actuallv agreed with tree growth; however, 



