good filtration of water, large and prolific trees may be found on 

 level land or even in depressions where water remains above the 

 surface a few hours after heavy rains. Mango trees are often found 

 on very light, unfertile sand, which may be a few feet in depth and 

 still produce flourishing growth if the subsoil is suitable. As the 

 mango, like most other fruit trees, thrives best on a deep, loose loam 

 with good drainage and a high percentage of humus, those who 

 intend planting it commercially should secure, if possible, this type 

 of soil. Imported mango trees planted on such land in Porto Rico 

 have reached a height of 26 feet and a spread of 34 feet in 12 years, 

 while others of the same variety, receiving an equal amount of rain- 

 fall litit growing in a soil with poor subdrainage, are at the same age 

 16 feet tall and 21 feet in spread. However, the latter have been 

 more prolific. 



CLIMATE. 



The temperature in Porto Rico is well suited to the production of 

 mangoes, for, as in other islands in this region, it is swept by warm 

 trade wind and sea breezes which keep it always warm enough for 

 the best growth of the trees. This is especially true in the low-lying 

 districts, those which lie between the sea and the mountains of the 

 interior having an average daily maximum temperature varying from 

 84° F. in winter to 89° in summer and a minimum from 66° F. in 

 winter to 73° in summer, an excellent temperature for the mango, 

 which is more tropical than subtropical in its needs. Through the 

 interior of the island the temperature averages from 2° to 3° cooler 

 during the day and from 5° to 6° cooler at night. At the highest 

 elevations, a number of which are over 2,000 feet, the temperature 

 during the coldest months is occasionally in the lower fifties. Here 

 the mango trees grow well but fruit very poorly, the small crops 

 probably resulting directly from the temperature. 



While the temperature is even and satisfactory, the rainfall and 

 general humidity vary considerably in different districts. In some 

 places, especially through the interior and along the northern slopes, 

 the rainfall is too great during the mango blossoming season for the 

 best fruit production. Along the western and southern coasts the 

 greater part of the year's rainfall occurs during summer and fall, and 

 during late winter and spring the rainfall is always light and the 

 drought usually severe. Here the crop of mangoes is almost invari- 

 ably heavy. The trees make a satisfactory growth unless the drought 

 is very long and severe, as they are capable of thriving on rather 

 slight moisture as well as of withstanding a little excess moisture 

 without visible injury. 



Where the drainage is good the only time at which the rains have 

 proved detrimental is while the trees are blossoming. Rains are 



