ENVIRONMENT 



105 



tendency to improve in smaller rings, and assuming some error in 

 tree No. 69, mean sensitivity is an excellent indicator of a tree's 

 accuracy in recording rainfall. Curve 4 hints that visual comparison 

 between curves of rainfall and tree-growth was not very different from 

 a mathematical correlation test. 



2.5 

 2.00 



1 1.5 

 1.0 



05 

 10 

 8 



2 6 



4 

 3 

 2 

 



3 4 -o 

 ao 



4! 'o 



.80 



.70 



.60 



/ 



/ 



, No; standardized^ 



M 



/>.. 



/ 



yj-T^-J-Stdndajrdiz ed \ 



trees 



Mean ring size 



>4'7 

 / 



Apparent mean 

 sensitivity 



Mean 

 sensitivity 



Visual comparison 

 with rain 



Correlation 

 with rain 



61 70 64 62 65 68 69 63 66 67 

 Tree number 

 Fig. 12 — Ring-size, sensitivity, and rainfall correlations, Prescott 



Sequoia contours and cycle lag — Variations in the smoothed 

 curves are much greater on the ridges than in the basins, where the 

 water-supply is far more abundant. The complacent basin curves 

 smooth out the shorter variations. A lag in the basin trees might be 

 expected, since the water takes time in getting there from the higher 



