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of generations is probably from 15 to 20, so that here, too, 

 these insects may become extremely abundant and do much 

 injury. They frequently suck the sap from the blossom buds, 

 sometimes preventing some of the fruit from setting, and 

 stunting and deforming many which do set. 



Plant lice are best controlled by spraying the trees thor- 

 oughly, just as the buds are opening, with nicotine sulfate, 

 40 per cent, 1 part, water, 800 parts. Two or 3 pounds of 

 common laundry soap can advantageously be added to each 

 50 gallons of this spray. If it is desired for any reason to 

 apply Bordeaux mixture or lime-sulfur at the same time, the 

 soap must not be put in. Spray through a very fine nozzle 

 and repeat ten days or two weeks later if aphids are still 

 present. 



The Leaf Hopper. 

 The leaf hopper, a tiny greenish insect not -\eiy much larger 

 than a plant louse, has been very injurious in apple orchards 

 during the last two or three years. It is found during the 

 spring months and again in the early fall mainly on the under 

 side of the leaves, sucking the sap and giving them a speckled 

 appearance, and in some cases drying them up and causing 

 them to turn yellow and fall off. In the particular cases 

 observed in this State, it does not seem to be the true apple 

 leaf hopper but an allied species, which does not cause a curl- 

 ing of the leaves to any such extent as the apple leaf hopper. 

 Lacking more complete, detailed knowledge of this insect, we 

 must rely on the general facts about the life histories of mem- 

 bers of this group to aid in determining when and how to at- 

 tempt control. In general, all the leaf hoppers for a time 

 suck sap from the plants on which they feed, growing and 

 by degrees developing wings. After a month, more or less, 

 of this, the wings become full sized, the insects mature 

 and they can then fly about. At this time they are much 

 harder to reach by spraying than earlier, so spraying should 

 be done when these insects first appear in the spring — while 

 they are young — and again in the fall under similar condi- 

 tions, taking them before they can fly, in each case. Nicotine 

 sulfate, 40 per cent, is known to be a good killing material for 



