TWENTY-FIRST REPORT OF STATE ENTOMOLOGIST 7 



by drainage. There are doubtless some localities where the ap- 

 plication of these remedies will afford relief, but it will take 

 the services of a person familiar with such work to direct the 

 operation and particularly to see in advance where such methods 

 will or will not be effective. 



THE SUGAR-BEET LEAF-HOPPER 



The sugar-beet leaf-hopper (Eutettix tenella Baker) is 

 without doubt the most serious insect enemy of the sugar beet, 

 and is of importance mainly because it is the means and the 

 only means of transmitting the very destructive disease known 

 as "curly top" or "curly leaf." It has caused periodic losses 

 to the sugar-beet growers and to the sugar companies of the 

 western states amounting to many millions of dollars. So 

 serious has the disease become in some of the western states 

 that the industry is seriously affected. Many beet sugar fac- 

 tories, costing from one million to two million dollars or more, 

 have been put out of business and closed. Some have been dis- 

 mantled and the expensive equipment moved elsewhere. 



In this connection an interesting situation has developed 

 during the last two years in Montana. Some of the companies 

 that have found it unprofitable to carry on their industry where 

 they are now located are looking to Montana as a field where 

 new factories can be established. In the spring of 1926 a rep- 

 resentative of a large company called on this office for assist- 

 ance in determining whether or not it would be wise to come 

 into the Missoula district with a factory. During July and 

 August a survey was made by one of the Experiment Station 

 entomologists and we were able to bring to the company's at- 

 tention facts that led to the conclusion that the beet leaf-hop- 

 per would not be a factor to prevent success here. This com- 

 pany is coming in with a factory. 



The survey referred to showed that this insect is present 

 in the district where the company is to operate but not in great 

 numbers, and a study of the natural conditions led to the con- 

 clusion that probably a profitable industry can be established 

 in spite of the leaf-hoppers. The conditions are very different 

 from those in the other western states where there has been 

 trouble. 



