2 BULLETIN 1073, U. S. DEPARTMENT OF AGRICULTURE. • 



that the trees are budded over to more promising varieties. At the 

 1920 spring meeting of the California Avocado Association more than 

 60 varieties of avocados were on exhibition. In a wise attempt to 

 restrain the commercial plantings of new varieties or strains which 

 have not been thoroughly tested, the association maintains a list of 

 those recommended for commercial use. The varieties now listed 

 are Dickinson, Fuerte, Puebla, Sharpless, and Spinks. Blakeman, 

 Lyon, and Taft, listed in 1919, have been dropped. Descriptions of 

 these varieties can be found in the annual report of the California 

 Avocado Association for 1917 and in the Manual of Tropical and 

 Subtropical Fruits, by Wilson Popenoe. 



PURPOSE OF INVESTIGATION. 



When it is desirable to harvest fruits or vegetables before they 

 mature, the problem of determining the time of their optimum 

 condition is seldom an easy one. It is particularly difficult in the 

 case of fruits that are raised at a great distance from their markets, 

 in which class belong practically all Pacific coast fruits. Much 

 difficulty has been experienced in trying to place these fruits in eastern 

 markets in a state satisfactory to the consumer, the tendency being to 

 harvest the fruit before it is ready, which results in putting a poor 

 and flavorless product in the hands of the consumer. 



While it is true that the avocado has not yet reached the stage of 

 development where it is being shipped to eastern markets in commer- 

 cial quantities, that time is fast approaching, and even now, under the 

 commercial methods of marketing it in California, knowledge of its 

 composition at maturity is imperative. Avocados are harvested 

 while hard and kept in storage at hotels, clubs, or markets until they 

 have softened. If picked too early the fruit has a tendency to 

 shrivel and become "rubbery," is watery, and lacks the characteristic 

 flavor of well-matured fruit. Its maturity problem thus assumes 

 special importance. Furthermore, this fruit is now in the first 

 period of its development, as far as the American market is concerned. 

 False impressions of its quality created at this time may greatly 

 injure its future. Already some adverse criticism of the avocado, 

 usually traceable to those who have bought immature fruits/ is 

 encountered. 



The composition of fruit of all of the varieties now grown and of 

 that from seedling trees brought into bearing each year, therefore, is 

 a matter of no little interest to the avocado grower. The work here 

 reported was undertaken for the purpose of throwing some light 

 upon the problems just enumerated. 



