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ANNUAL REPORT 1918 AND 1919 



trees will tend to bear moderate crops each year instead of an enormous 

 crop one year and nothing the following. There may be varieties, also, 

 which will not exhibit this tendency. But in general it is certainly a pro- 

 nounced characteristic of the Gutemalan race, and it does not seem to be 

 nearly so noticeable in the Mexican. 



The West Indian race, as observed in the Mexican lowlands, is not 

 altogether satisfactory in regard to productiveness. An examination of 

 numerous trees at Orizaba showed about half of them to be fruiting. 

 Whether it is a case of this same tendency to fruit in alternate years I 

 cannot say, as I have not yet had an opportunity to make sufficient observa- 

 tions on the question. I have noticed that large fruited varieties of this 

 race are particuularly unproductive. I have not seen a single one, in fact, 

 which seemed to be producing to the maximum of its ability. This is in 

 marked contrast to large fruited varieties of the Guatemalan race. I have 

 seen several of the latter in Guatemala which bore so many fruits that the 

 trees were not able to develop all of them to normal size. Many of them 

 had to drop off before half grown, or if they remained on the tree to ma- 

 turity they were small and stunted. 



The average age at which seedlings come into bearing differs notice- 

 ably among the races. We have had ample evidence of this in California, 

 insofar as the Guatemalan and Mexican are concerned. Under favorable 

 cultural conditions, I believe we can consider that the Mexican will com- 

 mence fruiting the third or fourth year from the seed, and the Guatemalan 

 the fifth to eighth year, usually not earlier than the sixth. The West In- 

 dian has not been so carefully observed, but I believe it is rare for it to 

 commence earlier than the sixth year. Here in the Tropics, where the 

 growth of the trees is slower, due to the lack of cultural attention, fruiting 

 probably commences from one to three years later than in California. If 

 good cultivation were given the trees, however, they would probably come 

 into bearing fully as early as in California, if not a year earlier in some 

 cases. 



The tendency to produce two crops a year, which has been noted in 

 California in the Northrup variety, seems to be a characteristic of the 

 Mexican race, though not present in all varieties. At Queretaro, in the 

 month of July, I observed a good many trees which were flowering and 

 setting new crops of fruit, although the main crop was just getting ripe and 

 the normal flowering season is not due until next February or March. This 

 secondary crop of fruit appears always to be a small one, by no means 

 equalling the main crop in quantity. I have never observed this habit of 

 fruiting twice a year in any of the other races. It seems to be limited to 

 the Mexican. 



The Crop: Season. Harvesting, and Marketing 



The season of ripening depends mainly upon two factors, race and 

 elevation. The Mexican race, which is justly entitled to be considered the 

 most important one in Mexico, though it is not so predominant as is the 

 Guatemalan race in Guatemala, commences to ripen on the central plateau 

 in the month of July, and continues until October or November. It re- 

 mains in season during a much longer period than does the West Indian in 

 the lowlands. Climatic conditions may account for a large part of this 

 difference. The most important months are August and September. In the 



