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Pomona College Journal op Economic Botany 



ment to remove the import duties or else promote the manufacture of them at 

 home; at any rate they surely ought to be offered for sale at the most reasonable 

 price possible. 



While it is true that in general these methods are necessary to the best suc- 

 cess of agriculture, yet local conditions must always be dealt with individually. 

 Field tillage that would bring about the best results in semi-arid soil might be 

 quite disastrous if applied blindly to a very humid soil. The duty of modern 

 science is to study the conditions affecting the growth of crops in as many localities 

 and under as may conditions as possible, not only in Mexico but in Southern Cal- 

 ifornia and everywhere else. 



Now let us turn to the methods of culture in orchard and other crops, having 

 seen those employed in cereal field preparation. The first thing one notices on 

 entering so-called orchards in Mexico is that nearly everything is left to the pro- 

 cesses of nature. Very little order is observed in the arrangement of the trees 

 and little effort is expended to keep the ground free from weeds. The soil is 

 seldom and poorly stirred, thus hindering seriously the bacteriological processes 

 of plant-food manufacture beneath the soil. Again, fertilization of the soil is al- 

 most never thought of. Because of the tremendous virgin richness of the soil the 

 idea is quite prevalent that culture is entirely unnecessary and uncalled for. It 

 has been only a comparatively short time since the California farmer and orchard- 

 ist has begun to realize that there is a limit to the virgin richness of our soils and 

 that this must be conserved most carefully and most scientifically, since personal 

 welfare as well as that of the state depends very largely upon it. The man who 

 ignorantly causes constant depletion of land or who greedily exploits it to its limit 

 is a menace to the nation, no matter where or who he may be. 



Very little or no effort has been made to improve orchard stock by budding, 

 grafting or selecting. What might be done in the way of improving the avocado, 

 for instance, or the mango, by breeding and selection is simply beyond estimate. 

 There is scarcely an avocado tree in the Republic, I venture, that is not a seedling, 

 and hardly a mango or orange tree that was not grown from a seed and left un- 

 improved. It is very good philosophy to be satisfied with what one has, but 

 only when that is the best that one can get. To be satisfied witli the products of 

 seedling trees is not in the least necessary since they can be improved and the 

 financial returns greatly increased simply by applying some of the scientific meth- 

 ods worked out in other countries. 



The avocado, or aguacate, grows in nearly all jjarts of the country and occurs 

 in many different varieties all the way from the size and the appearance of a small 

 plum or prune to a large full fruit some six inches in diameter. The meat varies 

 in quantity and quality from poor and insipid to rich and delicious. Yet in spite 

 of the immense range of varieties very little attempt has ever been made to im- 

 prove them or even select the best. It has been taken for granted apparently that 

 no other variety would flourish in any locality except those that have been there 

 for years. In recent articles on the "Avocado in Southern California" by Mr. 

 F. W. Popenoe the possibilities of improvement from budding and selection are 

 strongly brought out. It is a fact well known to horticulturists the world over 



