898.] ENTOMOLOGICAL NEWS. 91 



DEPARTMENT OF EGONOMIG ENTOMOLOGY. 



Edited by Prof. JOHN B. SMITH, ScD., New Brunswick, N. J. 



Papers for this department are solicited. They should be sent to the editor, Prof. John 

 B. Smith, Sc.D., New Brunswick, N.J. 



Quarantine Against Injurious Insects.— This question is perhaps the most 

 interesting and important in economic entomology to-day. Not only have 

 several States passed laws which require the inspection of all plants in- 

 troduced within their borders before they can be delivered to the pur- 

 chaser, or in lieu thereof a certificate which is supposed to show that they 

 have been inspected where grown and found free from injurious insects or 

 plant diseases; but there has been also introduced in both branches of 

 Congress a bill which provides for the exclusion of foreign fruits and plants, 

 unless accompanied by a similar certificate, or until they have been in- 

 spected at certain ports of entry to be designated by the Secretary of 

 Agriculture. Of course all these acts are in restraint or regulation of 

 commerce and only justifiable on the'ground of necessity. It seems per- 

 fectly clear that, after fruits or plants enter the boundaries of a State, they 

 become subject to its police regulations. It seems also clear that in so 

 far as the laws of a State require extra territorial action they are void. It 

 is for that reason that the power of Congress has been invoked to secure 

 legislation that shall be uniform. The desirability of restricting the dis- 

 tribution of plant pests is unquestioned; but it is by no means so certain 

 that the measures proposed will accomplish the result aimed at. 



In the first place, the question of diseases. Any one who has any 

 knowledge whatever of plant diseases knows that some of them may 

 exist for a considerable time in a latent state awaiting only favorable con- 

 ditions to develop. It is also known that some diseases can be only dis- 

 covered in certain stages of the plant's growth, and that when the leaves 

 are off, indications of peach yellows or peach rosette are practically indis- 

 coverable, except in very bad cases. Different causes also produce similar 

 results; thus starvation of a plant or an attack of root lice may produce 

 an appearance similar to the yellows, and it may require microscopic 

 examination to determine the question; hence an inspection that will 

 enable a man to say that a block of trees is or is not free from disease is 

 by no means a simple affair and not one that can be settled in the nursery 

 in all cases. 



Putting that aside for the present let us see how the insect question 

 stands, and leaving aside also the question of interstate commerce, let us 

 consider the question of the possibility of excluding injurious insects from 

 foreign countries. In his exceedingly interesting address before Section 

 F, at the Detroit meeting of the A. A. A. S., the vice-president, Dr. Le- 

 land O. Howard, handled the question of the spread of land species by 

 the agency of man with special reference to insects. He showed, most 



