LOSSES CAUSED BY IMPORTED TREE AND PLANT PESTS 



77 



mous citrus devel- 

 opment of Florida 

 and the Gulf Coast, 

 a disease which 

 Congress has joined 

 with the States in 

 an active effort to 

 exterminate w i t h 

 the aid of a large ap- 

 propriation. In ad- 

 dition to these more 

 important diseases, 

 many minor plant 

 diseases have also 

 been introduced. 



While, therefore, 

 much of the original 

 advantage which 

 the western hemi- 

 sphere enjoyed from 

 freedom from plant 

 pests has been lost, 

 there arc still vast 

 numbers of foreign 

 insect pests and 

 plant diseases with 

 large capacity for 

 harm which have 

 fortunately not yet 

 effected successful 

 lodgement in North 

 America or have 

 obtained only lim- 

 ited foothold and 

 may still possibly be 

 exterminated. 



P'or the informa- 

 tion of Federal and 

 State inspectors the 

 experts of the De- 

 partment of Agri- 

 culture have pre- 

 pared descriptive 

 lists of the known 

 plant enemies of the 

 world, insect and 

 fungous, which have 

 not yet reached the 

 United States or be- 

 come permanently 

 established therein. 

 A manual describ- 

 ing the dangerous 

 insects likely to be 

 introduced into the 

 United States, pre- 

 pared in the Bureau 

 of Entomology of 

 the Department of 

 Agriculture, and 



PESTS DETECTED LAST YEAR 



According to the report of the Federal Horticultural Board of the United States 

 Department of Agriculture, one hundred and ninety-three different kinds of 

 insects which might prove hurtful to American crops and one hundred and six- 

 teen plant diseases of similar significance were detected by State and Federal 

 inspection during the last fiscal year on plants and plant products offered for 

 import into the United States. 



Of the insects, fourteen were scale insects, such as Pear Scale, though they 

 range from scales found on Orchids, Cocoanut, and Bamboo to other forms found 

 on Wistaria, Camellias, Hemlocks and Pines. In addition, nests of the Brown- 

 tail Moth, egg masses of the European Tussock Moth, pupae of the Dagger Moth, 

 and cocoons of the Pine Sawfiy were discovered. 



Of interest was the finding of a fourth potato weevil in the United States, 

 which was discovered in Irish potatoes imported from the Andes. Of the 

 diseases, Citrus Canker was found in a number of shipments, and the find- 

 ing of Powdery Scab on wild potatoes from the east slope of the Andes is taken 

 to indicate clearly that it is the home of this disease of the potato. — Editor. 



VARIOUS STAGES OF THE GYPSY MOTH {PORTHETRIA DISPAR) 

 The gypsy moth is one of the worst forest pests of Europe. It was accidentally introduced into Massa- 

 chusetts 40 years ago, and has now spread to the adjacent States of Connecticut, Rhode Island, New 

 Hampshire, and Maine. It has been recently brought into this country on imported stock and taken 

 to such widely isolated points as Louisiana and Ohio. There is grave risk of its becoming distributed 

 over the entire United States. It has already cost in New England, in mere efforts at control, a good 

 many millions of dollars, and should it become widespread in the United States, damage from it would 

 be beyond calculation. 



now in press, lists 

 and describes over 

 three thousand dis- 

 tinct insect pests. 

 Proba1)ly half of 

 these are old-world 

 insects injurious to 

 forest and shade 

 trees, and the bal- 

 ance, insects injuri- 

 ous to various cul- 

 tivated crops. A 

 similar manual is in 

 preparation on the 

 fungous diseases of 

 the plants likely to 

 lie introduced into 

 the United States. 



Among the im- 

 jjortant insect pests 

 thus listed, which 

 we hope to exclude 

 from the American 

 continent, are such 

 notable examples as 

 the Mediterranean 

 fruit fly, perhaps 

 the most destruc- 

 tive of all fruit 

 pests; and the pink 

 boll worm of cotton, 

 recently spreading 

 from India to Egypt 

 and thence to prac- 

 tically every other 

 cotton- producing 

 country of the world 

 except the United 

 States — an insect 

 capable of doing 

 vastly greater dam- 

 age than the boll 

 weevil. Among for- 

 estry insects occur 

 such notable pests 

 as the "nonne" 

 moth of Europe, 

 which is as destruc- 

 live to conifers as 

 the gypsy moth 

 is in this country 

 to deciduous trees; 

 and many other 

 forest caterpillars 

 and bark-boring 

 and wood-boring 

 insects. 



There are also 

 known to occur in 

 foreign countries 



