February, '11] MARLATT: NATIONAL QUARANTINE 109 



these pests along the highways, and by this means check their more 

 rapid distribution. In spite of these efforts and this enormous ex- 

 penditure, these insects are still slowly spreading, and great damage is 

 done yearly to woodlands, private grounds, and orchards. The dis- 

 semination of these two pests over the whole United States, as is ex- 

 tremely likely under present conditions, would entail a like cost 

 throughout the country — a tremendous and unnecessary charge on 

 our fruit and forest interests. 



Very careful estimates, based on crop reports and actual insect 

 damage over a series of j^ears, show that the loss due to insect pests 

 of farm products, including fruits and live stock, now reaches the 

 almost inconceivable total of $1,000,000,000 annually. The larger 

 percentage of this loss is due to imported insect pests, and much of 

 it undoubtedly would have been saved if this country had early 

 enacted proper quarantine and inspection laws. 



DANGER OF ADDITIONAL IMPORTATIONS OF PESTS NEW TO THE UNITED 



STATES 



Great as is the number of foreign insect pests already imported and 

 established in the United States, there remain many others Avith equal 

 capacity for harm which fortunately have not yet reached our shores 

 or crossed our borders or at most have infested only a limited part of 

 our domain. The prominent examples of locally established pests, 

 the general spread of which should be controlled to the utmost, are 

 the gypsy and brown-tail moths. 



Our increasing business relations with China and other Oriental 

 countries adds enormously to the risk of the importation of new pests. 

 We know very little of the injurious insect pests of those countries, 

 and particularly of China, but the importation of new stock in the 

 last year or two, from China especially, has demonstrated the exis- 

 tence there of many pests which have not hitherto been known. The 

 power of harm of these new pests is abundantly illustrated l)}' the 

 San Jose scale which is one of the earliest of the Chinese insect pests 

 to reach us, and undoubtedly came to this country with some orna- 

 mental nursery stock sent from north China. 



Among the known foreign insect fruit pests which it is very desir- 

 able to keep out of this country are the Morellos fruit worm, which 

 is an important enemy of citrus fruits in certain parts of Mexico; the 

 olive fruit worm, which occurs throughout the Mediterranean coun- 

 tries where the olive is grown; the mango seed weevil, which has 

 been found in imported mango seed during the present year; several 

 fruit scale pests known to occur in China, Japan and other Oriental 

 countries, which have records for harm quite as great as the San Jose 



