412 THE MONTHLY BULLETIN. 



sistent pruning, and to the application of suitable fertilizers in ade- 

 quate quantities and in proper season ; and that if it be cultivated 

 negligently or not at all, it will not bear remunerative crops. It is 

 known that the olive in a state of nature is not exacting in respect to 

 soil ; it establishes itself on the sides of mountains, among clefts of 

 rocks and amid loose stones scarcely less well than in the richest and 

 best watered of garden soils. But when it comes to the cultivation of 

 the olive for profit, conditious of climate, soil, irrigation, tillage and 

 fertilization have to be carefully studied. 



It has been demonstrated that the olive will thrive best in a light, 

 friable, well aerated, warm and well — but not necessarily deeply — 

 drained soil, rich in lime and potash, and that it will yield scanty crops 

 of fruit of poor quality in heavy, clayey or ill-drained soils. The olive 

 requires less water than many other trees, on account of its sparse 

 foliage and strong root system. It will not, however, produce heavy 

 yields in a soil lacking in moisture. Excepting in rare cases, monthly 

 irrigation during the dry season is necessary for big fruit and regular 

 yield. This must not, however, be excessive, and the water level must 

 be kept low, otherwise the quality of the crop will be inferior, the yield 

 irregular and the tree subject to disease. In many rich, loamy soils, a 

 good tree growth can be obtained without irrigation, but inequalities 

 and intermittency of yield, to which the olive is subject under cer- 

 tain conditions, make the growing of the product unprofitable in these 

 localities. 



In the coast regions of California subject to the fog and cool sea 

 breezes, the tree is generally diseased, the yield irregular and the fruit 

 of poor quality. A dry, warm atmosphere is absolutely essential. 



It is unwise to plant olive trees in any region where the temperature 

 often falls below 20 degrees. The olive tree has survived a temperature 

 of 10 degrees in California, but the fruit may be injured by a fall in 

 temperature to 28 degrees. This tends to render unprofitable the groM'- 

 ing of the olive in localities where the ripening season extends into the 

 later winter months. Thus the climate restricts the district available 

 for olive culture. 



In soil, climate and varieties, the experimental stage has been passed, 

 and the olive industry occupies a peculiarly secure position. 



There are approximately 25,000 acres of olives — bearing and non- 

 bearing — in California. This is only a small fraction of the acreage 

 in peaches, prunes, apricots, apples or oranges, for instance, in Cali- 

 fornia; and these products are grown in other states, and in other 

 countries throughout the world, while California alone produces prac- 

 tically the entire world crop of pickled ripe olives; and on account of 

 the combination of climatic and soil conditions, the future production 

 of the pickled ripe olive commercially will practically be confined to 

 . California. 



There are thousands of acres of land in the foothill sections of 

 northern and central California, where climatic and soil conditions are 

 ideal for olive culture, that would not grow any other product profit- 

 ably ; and olive growing is especially attractive for many reasons. The 

 olive is the only fruit bearing tree whose producing qualities do not 

 deteriorate with age. In fact, they appear to increase as far as we have 

 any record. Many olive trees in California, which are known to have 



