FEDEKAL HORTICULTURAL BOARD. 631 



tables from Mexico, Central America, the West Indies, and certain 

 other countries. It may be noted that the fruits which enter most 

 largely into our imports, such as bananas, lemons, grapes, etc., are 

 open to unlimited entry. Naturally, the quarantine bears most 

 strictly on those tropical and subtropical countries in which fruit 

 flies are known to be most thoroughly established and the fruits and 

 vegetables from which would therefore have a peculiar risk to this 

 country. 



That the danger of entry of important fruit fly and other pests 

 in connection with imports of fruits and vegetables is a very real 

 one is clearly indicated by the many interceptions of infested fruits 

 and vegetables which have been made at various ports of entry, both 

 by Federal and State inspectors. Many of these interceptions have 

 been in connection with fruits brought in by passengers or by ships' 

 crews or as a part of ships' stores, but others have been in connec- 

 tion with commercial shipments. Except as to the ports of Cali- 

 fornia and Florida, and in very recent years New Orleans, no thor- 

 oughgoing insj)ection has been maintained of fruit and vegetable en- 

 tries. Tliat this country has not become invaded by fruit flies is 

 therefore more a matter of good fortune than otherwise. 



The danger is, furthermore, a rapidly growing one with the in- 

 crease of world commerce and especially with the shortening of time 

 between countries by the building of speedier ships. As an example, 

 it is now possible to send fairly perishable fruit, such as peaches, 

 apricots, melons, etc.. from South Africa to New York and to have 

 such fruit cross the continent to San Francisco. A portion of a 

 shipment of nectarines so routed from South Africa was intercepted 

 in California and found infested with fruit-fly larvae. It is known 

 also that various foreign countries invaded with fruit flies are mak- 

 ing preparations to increase their fruit and vegetable exports to 

 the United States, and some of the shipments which have already 

 reached us from such countries, as just noted, have proved to be in- 

 fested with fruit flies. The risk which will follow the more frequent 

 and larger shij^ments which are in prospect is evident, and the ne- 

 cessity for taking prompt measures to protect the American fruit 

 cultures from these pests would seem to require no argument. 



Perhaps the most destructive of all the pests of fruits and vegeta- 

 bles are the various fruit flies which have gained foothold more or less 

 widely throughout the tropical and subtropical regions of the world 

 other than in the United States. In various countries these pests 

 have caused tremendous losses to nearly all classes of fruits and vege- 

 tables, often preventing the further profitable production of such 

 •crops. While they are particularly disastrous in subtropical and 

 tropical countries, their range as determined by temperature would 

 include the citrus areas of the United States and probably extend 

 far northward into the peach, prune, apple, and other deciduous fruit- 

 producing areas. 



EXPLORATION AND RESEARCH WORK. 



During the year the board has conducted, in cooperation with the 

 appropriate bureaus of the department, important research work, 

 notably with respect to the pink bollworm of cotton, potato- wart 

 •disease, and the date scale. 



78007— AGK 1923 41 



