REPORT OF THE SECRETARY OF AGRICULTURE. XXIX 



ing lands; hence, experiment stations established there must be so 

 organized as to be an integral part of the Department. In order to do 

 this the stations should be put in charge of men from the Department 

 who are familiar with existing conditions and whose knowledge will 

 render them strong supporters of the Department's work. This policy 

 has already been carried out in the case of the stations established in 

 Hawaii and Porto Rico. The tropical work proper of the Department, 

 therefore, will be along the lines already laid down, and wherever 

 practicable will be carried on in cooperation with the stations estab- 

 lished, whose energies, for a number of years at least, must be; devoted 

 to matters more or less local. 



The improvements in the coffee industry of Porto Rico are an exam- 

 ple of what has already been accomplished in this direction. Among 

 the agricultural imports of the United States, coffee is second only to 

 sugar, our annual importations averaging $70,000,000, and only a 

 small fraction of 1 per cent of this quantity comes from our tropical 

 islands. The most important industry of Porto Rico, however, is the 

 raising of coffee for European markets; hence, it has received early 

 attention in our investigations of tropical agriculture. It has been 

 found that the Porto Rican coffee plantations are seriously injured by 

 being too heavily shaded, and also that shade is not, as commonly 

 believed, a necessity, the supposed good effects resulting from it con- 

 sisting simply in the fixation of nitrogen in the soil by the root tuber- 

 cles of the leguminous trees used for shade. The other advantages of 

 shade are only indirect, consisting in the protection of the soil from 

 heat, drought, and erosion. Rational moderation in the use of shade, 

 the raising of seedlings in nurseries, and other practical cultural 

 improvements would double or treble the island's output of coffee, 

 and with the increase of acreage readily possible for this crop the 

 island could be made to produce more than half of the coffee con- 

 sumed in the United States. The work now under way is planned to 

 bring this about, and encouraging results have already been obtained. 



GRASS AND FORAGE PLANT INVESTIGATIONS. 



The problems involved in the investigations of grass and forage 

 crops are some of the most important that to-day confront the Ameri- 

 can farmer. As population increases and competition in all lines of 

 agricultural work becomes keener, the need becomes strongly felt for 

 more light on such important questions as: How to restore the great 

 ranges of the West; how to maintain our pastures; how to meet the 

 trying conditions in the South and semiarid West in supplying food 

 for stock, etc. The work of the Agrostologist is conducted with a 

 view to solving these problems, and already very encouraging and 

 promising results have been obtained, some of which may be referred 

 to here. 



