CITRUS CULTURE IX PORTO RICO 



3 



price of oranges, caused many growers to make new plantings or to 

 rebud the trees already planted ; as a result, very few orange groves 

 are to be found in Porto Rico to-day. 



The introduced grapefruit varieties, like the orange varieties, 

 comprised practically all that were grown at the time in Florida. 

 Types resembling the Duncan seem to have predominated, and the 

 Duncan and the seedless varieties apparently have been preferred 

 in later propagation work. To-day only these two varieties are 

 recognized. The seeded type is locally known as the Duncan re- 

 gardless of visible differences, and the seedless, or nearly seedless 

 t}^pe, is called " Marsh Seedless." The variation found in most of 

 the groves is considerable, and would seem to point toward a profit- 

 able field for selection. 



The first groves were started by continental Americans, only a 

 few of whom had had experience in citrus growing. Their experi- 

 ence had been gained in Florida, and as a result an attempt was 

 made to apply Florida methods to Porto Eico. Many of the meth- 

 ods, such as low budding, deep planting, and growing the trees 

 without wind protection, proved to be great handicaps to a success- 

 ful industry from the very beginning. Efforts to combat gum 

 disease, scale insects, ants, leaf-eating beetles, and root-eating grubs 

 were costly and discouraging. As experience was gained these diffi- 

 culties were overcome, but many of the surviving trees have re- 

 quired constant attention ever since. Because of these early mis- 

 takes the annual loss of trees in Porto Rico has been abnormally 

 high. During the past 10 years many of the most productive trees 

 have died from root rot and from gumming induced by low plant- 

 ing. The life of some of these trees has been greatly prolonged by 

 inarching and by the judicious use of tree surgery, but most of them 

 were destroyed by the hurricane of 1928. Thousands of healthy 

 trees were blown over. Those which were promptly set up and 

 properly cared for usually recovered, but many trees in the mountain 

 districts were lost as the result of neglect. 



ANNUAL SHIPMENTS OF FRUIT 



Production per tree is difficult to estimate, and the average yield 

 per tree can not be stated because some trees yield 10 to 20 boxes of 

 fruit, whereas others yield nothing. Of the latter kind, some may 

 not have reached bearing age, and others may be nonbearers or 

 practically so. The export figures for oranges can give no clue 

 to the yield per tree because oranges from the mountain districts 

 are shipped only when prices warrant, and the island consumption 

 is always uncertain. The census report of 1920 showed that there 

 was then a total of 1,300,000 orange trees on the island. A compari- 

 son of this number of trees with the number of boxes of oranges 

 exported in 1918 reveals a yield of less than half a box of fruit per 

 tree, and similar comparisons show that in other years the yield 

 was one-quarter of a box of fruit or less per tree. Notwithstanding 

 these facts, the seedling trees are usually very prolific. 



Table 1 gives the annual shipments of citrus fruits from Porto 

 Rico for the period 1910-1928, inclusive. 



