16 DROUGHT RESISTANCE OF OLIVE IN SOUTHWESTERN STATES. 



excellent growth, but with the failure of the water every one of them 

 has died. On the right are seen the olive trees still making a good 

 growth. A few pomegranate bushes and pepper trees planted in the 

 dooryard adjacent to the olives, while nearly all living, have appar- 

 ently suffered more seriously from drought than the olives. 



DRY-LAND OLIVE TREES NEAR PHOENIX, ARIZ." 



A few miles northeast of Phoenix, Ariz., a tract of land was laid off 

 into a sort of residence park under the name of "Las Palmas."'' 

 Numerous avenues and drives were planted with Canary Island 

 palms, pepper trees, and other ornamentals, and at the same time a 

 considerable number of olive trees was set out, a row along the south 

 side of the southeast quarter being half a mile long. Owing to diffi- 

 culties about the water supply, cultivation and care ceased over all 

 but a small part of the tract, so that for the past six years no irriga- 

 tion has been given the olives and peppers on the south side of the 

 section and only a small amount to some of the palms. 



The soil here, though gravelly, is much richer in clay and fine silt 

 than that of the Casa Grande tract. This portion of section 22 has 

 for several years been heavily pastured by horses, cattle, and sheep, 

 the trampling of this stock being sufficient to render the ground 

 around the row of olives smooth and compact, so that much of the 

 rainfall would be turned off instead of being caught and allowed to 

 percolate to the roots. A much better supply of forage seems to have 

 prevented the stock in this pasture from browsing the olives as 

 severely as was done at Casa Grande, though apparently sheep have 

 fed off the leaves and small twigs to a height of about 4 feet. 



We find this to be a case of growth under decidedly adverse condi- 

 tions, though not the most extreme. The row of olive trees along the 

 south side of the section is uneven in growth, but many are 12 to 

 15 feet high, with trunks from 5 to 7 inches in diameter. Here, 

 as in other droughty situations, the olive has a strong tendency to 

 put out sprouts from near the base, thus protecting the trunk from 

 the heat of the sun. This universal habit of olive trees in dry locali- 

 ties, even those that have been headed high enough to expose the 

 trunk, points clearly to the desirability of a method of pruning which 

 will provide a low, spreading head, thoroughly protecting the trunk 

 and main branches. 



That several of the trees in this south row should have fruited in 

 1907 in the face of such privation and neglect, though producing only 

 a light crop, is strong evidence of the hardiness and drought resistance 

 of the olive. 



« See map, figure 1. b Comprising section 22, in township 2 north, range 3 east. 

 192 



