NO. l8 TREE GROWTH AND RAINFALL CLOCK I7 



1897 to that of 1898-1941. The individual trees of group 10 are not 

 consistent among themselves in that HPC i and 3 increase decidedly, 

 HPC 2 increases very slightly, and HPC 7 decreases. All trees in 

 group II are consistent except for HPC 6 which decreases very 

 slightly. Thus, four trees decrease, two remain practically unchanged, 

 and two increase their average thicknesses for the period 1 897-1 941 

 contrasted with that of 1850-1897. Group 7 reflects these influences. 



Table 5 — Holnian Pass collection 

 Average groicth-laycr thicknesses 



i8g8 i8so i8q8 



1° to to to 



if^Q/ 1941 i8g7 1941 



HPC 1 1850- 1.28 1.82 G 10 1.53 i.;o 



2 1850- 1.87 1.88 II 2.26 1.96 



3 1850- i.oi 1.23 7 1.90 1.83 



4 1880- 3.50 2.95 



5 1850- 1. 18 0.79 



^' 1850- 1.52 1.51 



7 iSjO- 1.96 1.86 



9 1861- 2.85 2.61 



Table 6. — Holman Pass collection 

 Average departures 



1898 i8so 1808 



to to to to 



1897 I94I 1897 IQ4I 



HPC 1 1850- 0.31 0.36 G 10 0.32 0.36 



2 1S50- 0.32 0.27 11 0.34 0.30 



3 1850- 0.4s 0.42 7 0.18 0.20 



4 1880- 0.37 0.36 



5 1850- 0.39 0.34 



6 1850- 0.27 0.21 



7 1850- 0.19 0.38 



9 1861- 0.31 0.28 



In Table 6, group 10 shows an increase and group 11 a decrease of 

 average departures from the period 1850- 1897 to that of 1 898-1 941. 

 All trees of group 11 are consistent among themselves in the decrease 

 from the earlier to the later period. This is not true for the trees 

 of group 10. Two of them, HPC 2 and 3, actually showed a decrease 

 of average departures and thus conformed with the wet-site trees of 

 group II. In other words, trees HPC i and 7 do not conform with 

 the remaining six trees, yet their influence is sufficiently great to 

 determine the relative values as shown for groups 7 and 10 in table 6. 



