68 



as azaleas and rhododendrons), and a long list of plant material 

 commonly known as florists' stock. 



Excluded plants may still be imported through the agency of 

 the Department of x^griculture, in limited quantities to supply 

 the country with novelties and necessary propagating stock, such 

 entry being safeguarded by the highly-developed inspection and 

 quarantine service which has been organized l3y the department. 



The governing principle in this quarantine is to limit plant in- 

 troductions to the classes of plants which have been represented 

 by the plant interests concerned in this country as being essential 

 to plant production — in other words, the raw material out of 

 which salable fruit trees, roses, etc., are made. To these were 

 added certain classes of plants, including bulbs and seeds, which 

 could be safeguarded by inspection and disinfection. 



The plants permitted entry represent a considerable proportion 

 of foreign plants and seeds hitherto imported, but exclude the 

 classes of plants, including all plants with earth, which are open 

 to special danger of importing new pests. The excluded plants 

 are largely ornamentals imported to be turned over at a quick 

 profit, and, on the authority of the experts of the department and 

 of leading plant growers, can be produced for the most part in 

 sufficient quantities in this country. 



DANGEROUS BULBS EXCLUDED. 



In the case of bulbs it was realized that a danger existed and 

 the entry was restricted to classes of bulbs least subject to risk of 

 bringing in new pests and which from their nature could be most 

 readily inspected and determined as clean. The excluded bulbs 

 involve the less important and miscellaneous importations coming 

 from widely scattered sources and the entry of which is attended 

 with greater risk of introduction of plant diseases and insect 

 pests. 



Disinfection by any known means is not possible in the case of 

 most of the ornamental plants excluded, and particularly those 

 which come with soil about the roots. No disinfection of soil is 

 possible without destroying the plants, and, furthermore, many 

 insects and practically all diseases are not capable of control by 

 disinfection and are not disclosed by inspection. This condition, 

 requiring removal of soil and holding in quarantine for consid- 

 erable periods, as is done in case of departmental importations, 

 precludes safeguarding of importations on a commercial scale. 



DANGER IN UNKNOWN PESTS. 



The number of known foreign pests awaiting entry to the 

 United States is vastly larger than those which have already 

 gained entrance, and the unknown foreign pest is an uncertain 

 quantity, perhaps more dangerous than the known pests, officials 

 point out. 



The risk is illustrated by recent introductions — for example, the 

 alfalfa weevil, the oriental peach moth, the Japanese beetle, and 

 the citrus canker, together with such older importations as the 

 San Jose scale, the brown-tail moth, the chestnut-blight disease 

 and the white-pine blister rust. 



