CONTENTS. 



PAGE 



INTRODUCTION 119 



SPECIES OF WALNUT. 



THE ENGLISH WALNUT 128 



AMERICAN BLACK WALNUT (Juglans nigra) 128 



CALIFORNIA BLACK WALNUTS 128 



NORTHERN CALIFORNIA BLACK WALNUT 129 



SOUTHERN CALIFORNIA TYPE 138 



Relationship Between the Southern and Northern California Types of 



Black Walnut 141 



OTHER NATIVE WALNUTS OF THE SOUTHWEST 146 



NATIVE WALNUTS OF ARIZONA 147 



NATIVE WALNUTS OF TEXAS 149 



NATIVE WALNUTS OF NEW MEXICO 150 



THE BUTTERNUT (Juglans cinerea) 151 



FOREIGN WALNUT SPECIES 152 



Juglans sieboldiana 152 



Juglans cordiformis 152 



Juglans mandshurica 152 



Juglans 'bolimensis 152 



Pterocarya caucasica 152 



HYBRID WALNUTS 152 



PARADOX HYBRIDS 154 



Seedlings of Paradox Trees 162 



ROYAL HYBRID WALNUTS 163 



Seedlings of Royal Trees 167 



FREAK WALNUT TREES 168 



FOSSIL WALNUT SPECIES 171 



WALNUT CULTURE IN CALIFORNIA 171 



HISTORY 171 



LOCATION FOR WALNUTS 176 



Climate 176 



Frost 176 



Heat 177 



Soil __. 178 



DISTANCE OF PLANTING 179 



Interplanting 179 



CULTURE 182 



Soil Handling 182 



Irrigation 183 



Fertilization 185 



Pruning 189 



CROP HANDLING 192 



Picking 193 



Washing 193 



PACKING-HOUSE OPERATIONS 195 



Sampling 195 



Bleaching 196 



Grading 197 



Walnut Grades 198 



Selling 199 



