CONTENTS. 



Page. 



Introduction 9 



Dry-land olive investigations 10 



Examples of drought resistance of the olive in the United States 10 



An abandoned olive grove at Casa Grande, Ariz 10 



The Bogart-Degolia olive grove 13 



Dry-land olive grove near Florence, Ariz 15 



Dry-land olive trees near Phoenix, Ariz 16 



The Pope olive plantation, near Palm Springs, Cal 17 



Description 17 



Climate of Palm Springs 18 



Soil at Palm Springs 20 



History of the grove 23 



Present condition of the grove 24 



Olive root systems adapted to utilize limited rainfall 27 



Moisture economy aided by the structure of the olive leaf and stem 30 



Successful dry-land olive culture in California 31 



Area of possible dry-land olive culture in the United States 34 



Area limited by the minimum temperature 34 



Area limited by heat requirements 37 



Area limited by rainfall 41 



Summary 42 



APPENDIX. 



Anatomical structure of the olive {Olea europea), by Dr. Theo. Holm 47 



Root structure of the olive 47 



Leaf and stem structure of the olive 49 



Description of plates 56 



Index 57 



192 5 



