CONTENTS 



PAGE 



I. Introduction 3 



Affiliations 3 



Development 4 



Cooperation 5 



Acknowledgments 6 



Previous work 7 



II. Tree selection 8 



Species 8 



Location: grouping, soil, topography, 



altitude 12 



Condition: injuries, fire scars 14 



Collection purposes: cycles and secu- 

 lar changes, age estimates 15 



III. Radials 17 



Selection 17 



Living trees: place and direction of 



boring 17 



Fallen trees 19 



Stumps: v-cut and its location 19 



Preparing the radial 21 



Radial studies 22 



Circuit uniformity: eccentricity, 



lobes and gross rings 22 



Vertical uniformity: tests at 



different heights 24 



IV. Rings 28 



Selection in group 28 



Mean conformity 28 



Mean sensitivity 29 



Selection within record 30 



Parts of tree's record: infancy, 



youth, maturity, age 30 



Ring errors : superfluous, missing, 



reinforced, and false rings 31 



V. Instruments and technique 34 



Collecting tools : saws, borers, paraffin 



treatment 34 



Measuring instruments 37 



Early forms 37 



Plotting micrometer; auto-plot . . 37 



Longitudinal plotter; long-plot. . 39 



Clerical operations 40 



Standardizing 40 



Cycle plots: skeleton plots, 



smoothing, Hanning 42 



The cyclograph (periodograph) 45 



Comparison of analyzing methods 45 



Principle of the cyclograph 46 



The White cyclograph 47 



Cycloscope 50 



VI. Tree records: length 51 



Old sequoia records 51 



Third sequoia trip, 1919 51 



Fourth sequoia trip, 1924 52 



Fifth sequoia trip, 1925 54 



Coast redwood records 55 



Santa Cruz group, 1921 55 



Scotia trip, 1925 55 



Deficiency of the coast redwood 56 



PAGE 



VI. Tree records: length — continued 



Old pine records 57 



Search for old trees; 500- and 



640-year pines, burnt centers . 57 



Prehistoric material 59 



California and Arizona cross- 

 dating 61 



Charleston Mountain trip 61 



VII. Tree records: geographical dis- 



tribution 63 



Western circuit, 1925 63 



Western contours and rainfall ... 64 



The three zones 64 



The Pueblo area 65 



Southwestern contours 66 



Western pine groups: statistics and 



treatment 67 



Arizona region 68 



First Flagstaff group 68 



Flagstaff 500-year group 69 



Fort Valley group 69 



High-level group 71 



Flagstaff shadow group 71 



Flagstaff northeast group 72 



Grand Canyon group 72 



Dixie Forest (Utah) group 73 



Upper Rim group 73 



Lower Rim group 74 



Cibecue group 74 



Pinal Mountain group 75 



Catalina Mountain group 75 



Santa Rita group 76 



The Rocky Mountain zone 77 



Yellowstone group 77 



Laramie, Wyoming, group 77 



Clements's Pike's Peak group . . 77 



Pike's Peak Timberline group . . 79 



Pike's Peak Basin group 79 



Upper North Transect group ... 79 



Lower North Transect group ... 80 



South Transect group 80 



Brook group of Douglas fir ... . 80 

 Brook group of Engelmann 



Spruce 81 



Cloudcroft, New Mexico, group. 81 



Santa Fe group 82 



Basin Mountain Upper group ... 82 



Basin Mountain Lower group ... 83 



Aztec East group 83 



The Coast zone 83 



Boise, Idaho, group 83 



Baker, Oregon, group 85 



Dalles group 85 



Oregon Coast group 85 



Klamath Falls group 86 



Plumas County group 86 



Calaveras group of pines 87 



Big Creek group 87 



Springville group of pines 88 



Mount Wilson group 88 



