VI 



CONTENTS 



PAGE 



VII. Tree records: geographical dis- 



tribution. The Coast zone — 



continued 



San Bernardino group 89 



Charleston Mountain group .... 89 



Pine Valley group 90 



Miscellaneous groups 90 



Sequoias 90 



Coast redwoods 91 



Arizona groups 91 



Other western groups 91 



North American groups 92 



Foreign groups 93 



VIII. Environment 94 



Effects in trees 94 



Climate : single and double rings . 94 



Rainfall correlations: Prescott, 

 Flagstaff, Cibecue drought 



record; sequoia 97 



Conservation: reversed and dis- 

 torted effects 10° 



Other climatic correlations; wind 102 



Topography 102 



Sequoia topography: ring type 

 and moisture, sensitivity and 



cycle lag 103 



Pike's Peak topography; kind 



of tree I 06 



San Francisco Peaks; altitude, 



shadow effect, and soil 107 



Changing conditions : shade, drain- 

 age, soil, and grouping 110 



Environment indicators Ill 



Evidence in individual rings .... Ill 



PAGE 



VIII. Environment. Environment indi- 



cators — continued 



Evidence in single trees Ill 



Changing ring-size 112 



IX. Cycles H3 



Cycle origins 1 13 



Solar theory: sunspots, rotation, 



radiation 113 



Terrestrial reaction: tempera- 

 tures, droughts, electrostatics, 

 glacial varves, ocean rotation, 



etc H5 



Cycles in tree-growth 117 



Cycle reliability: short and long 



cycles, criteria and tests 117 



The periodocrite 1 19 



Zone centers and their mean 



curves 120 



Meteorological areas; the prob- 

 lem of combination 122 



Cycles in western zones: arcigram, 

 zone summaries, sequoia cycles 123 

 Solar records in tree-growth ; histori- 

 cal confirmation, dearth cycles, 

 wet and dry climatic effects. . . . 125 

 Solar cycles, historical changes, cli- 

 matic patterns 127 



Cyclograms 130 



Cycles and climate; cautions; possible 



future Flagstaff variations 133 



Summary 136 



Appendix 139 



Tables or group averages, standard- 

 ized 139 



Bibliography 159 



