CHANGES IN COMPOSITION OF CALIFORNIA AVOCADOS. 3 
INVESTIGATIONAL WORK. 
METHODS OF SAMPLING. 
It has been somewhat difficult to get satisfactory trees from which 
to obtain samples. Orchards are still too few to afford much choice. 
For satisfactory data upon which to base opinions of either maturity 
or average composition, samples of each variety should be secured 
from each of several districts throughout the State. 
Ideal conditions can be secured only where each variety is found 
growing in the same orchard, thus being exposed to the same climatic 
conditions and receiving identical cultivation. As some growers 
neither cultivate nor fertilize their trees, while others do both, it is 
well within the realm of possibility that the same variety of fruit 
grown under such varying conditions will differ markedly in compo- 
sition and maturity. While conditions at the time this work was 
undertaken were far from ideal, the knowledge gained by any experi- 
ment goes far in guiding the industry along the right paths. 
A single tree of each of the eight varieties recommended by the 
California Avocado Association in 1919 2 was selected, in a location 
where orchard conditions existed, without regard to climatic condi- 
cions. Each location was in a district where the avocado is commer- 
cially grown. 
The trees were located as follows: The Blakeman at Altadena, the 
Dickinson at Chula Vista, the Fuerte at Yorba Linda, the Lyon at 
Whittier, the Puebla at San Fernando, the Sharpless at Tustin, the 
Spinks at Duarte, and the Taft at Yorba Linda. This list shows a 
wide distribution of locations, each growing district of California 
being represented with the exception of Ventura and Santa Barbara 
Counties. 
All of the fruit on the trees, which were voung, strong growing 
specimens, bearing from 25 to 75 fruits, was reserved for samples. 
Although most of the locations were in secluded areas, a great deal 
of the fruit was stolen. Loss in one location was caused by wind 
storms. 
Depending on the number of fruits on the tree, samples consisting 
of from one to six fruits were sent to the laboratory for analysis at 
monthly intervals. When possible the samples were divided at the 
laboratory into equal subdivisions, one of which was analyzed at 
once, the other being wrapped in paper and permitted to soften at 
room temperature before analysis. Whenever it was necessary to 
store samples after they were ready for analysis, they were held at 
a temperature of from 35° to 45° F. The samples analyzed at once 
are here designated "fresh samples/' the others, "storage samples. " 
2 Three of these varieties have since been taken from the list because of alleged faults in the trees or 
fruits. These faults, however, had no bearing on the composition of the fruit. 
