84 MAINE AGRICULTURAL EXPERIMENT STATION. I915. 



ous fungus diseases, blights, etc., so that the diestructive possi- 

 bilities are much more serious. 



'The willows are also very generally infested by several 

 species of Idiocerus, Pediopsis, Binpoasca, and S caphoideus 

 occurring on these and some of them being restricted very 

 closely to the willow family and in some cases depending upon 

 particular species of this family for their subsistence. While 

 these trees are at present of rather small oommercial value 

 their possible value for the making of paper pulp is likely to 

 bring them into importance in the future. 



The commo'n alders also support a number of distinct forms 

 of leafhoppers and while the value oi this plant is of minor 

 importance as furnishing any particular product, the common 

 occurrence of the clumps and their distinct place in the landt- 

 scape renders them of no small account. 



METHODS OF CONTROL. 



There are certain methods of control that may be applied to 

 the various kinds of leafhoppers and a general statement of 

 these may serve to avoid repetition for each s,pecies. These 

 methods vary of course for the different groups and may also 

 be affected by local conditions or special methods of cultivation. 

 thaJt may be in vogue for ceritain crops or for certain localities. 



Crop rotation is one of the general measures that is of ser- 

 vice here as for many other insects and it may be assumed that 

 the general practice of rotation in co'nnection with a number 

 of the field crops is a probable reason that the leafhoppers are 

 no more injurious to such crops as o^ats and potatoes. 



Clean culture is a!lso to be credited with the reduction of 

 numbers for many species, especially those vvhich develop upon 

 annual plants and migrate tO' adjacent fields. The careful 

 attention to destruction of such weeds as fox-ftail, witch-grass, 

 crab-grass, etc., must have a decided effect on the abundance of 

 the species that work readily on timothy and other pasture or 

 meadow grasses. 



Mounng is a measure that may be resorted to for the reduc- 

 tion of meadoav species but its greatest usefulness must depend 

 on timing the cutting to the period of greatest abundance of 

 eggs or of very young larvae. 



