DESCRIPTION OF PLATES. 



Plate I. Fig. 1. — One of the larger olive trees on the Bogart-Degolia plantation 

 near Casa Grande, Ariz. Fig. 2. — Olive trees in the "Las Palmas" section, near 

 Phoenix, Ariz., after six years of neglect and lack of water. 



Plate II. Fig. 1.— View in the Florence, Ariz., olive grove, about 16 years old, which 

 has had no irrigation for the past six years. At the left, dead apricot and almond 

 trees of the same age; at the right, olive trees in vigorous condition. Fig. 2. — 

 Interior view in the grove shown in figure 1, showing a fine growth but thinner 

 foliage than in the outer row shown in figure 1, due to the crowding of the trees. 



Plate III. Fig. 1. — Viewin the Pope olive plantation, near Palm Springs, Cal., after 

 six years of neglect. Mean annual rainfall only 3 J inches. Fig. 2. — One of the 

 larger trees, 8 feet high, in the Pope olive plantation, showing the low habit of 

 growth and the protection of the trunk and main branches from heat by a canopy 

 of foliage. 



Plate IV. Fig. 1. — Characteristic burl at the base of an olive tree on the Pope olive 

 plantation, near Palm Springs, Cal. Fig. 2.— Feeding rootlets, natural size, from 

 6 inches in depth, on the same plantation shown in figure 1. 



Plate V. Fig. 1. — Cross section of the midrib of the leaf of Olea europea (Mission 

 variety), showing the epidermis, palisade tissue, massively developed coUen- 

 chyma, pericyclic stereome, hadrome, leptome, and pneumatic tissue. Mag- 

 nified 180 times. Fig. 2. — Cross section of one of the apical internodes of the 

 stem, showing the epidermis, hypodermal collenchyma, stereome ring, leptome, 

 hadrome, and pith. Magnified 112 times. 



Plate VI. Fig. 1. — View in a 500-acre olive plantation in southern Los Angeles 

 County, near La Mirada, Cal., grown without irrigation. The planting distance 

 of 20 feet each way is much too close for the full development of the trees. 

 Fig. 2. — View in a different part of the plantation shown in figure 1, where the 

 trees have been thinned by removing alternate diagonal rows. The conditions 

 are consequently much improved. 

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