ENTOMOLOGY 59 



Distillate-oil emulsions at 6 per cent strength and crude-oil 

 emulsion at 12 per cent strength, measured by their efficiency against 

 scales and lichens, convenience of preparation and application and 

 cost, are the sprays best adapted for the European fruit Leca- 

 nium. All sprays, to insure the best results, should be applied With 

 a power outfit at a high pressure (180 to 200 Ibs.). A coarse, drench- 

 ing spray applied with a crook nozzle is preferable, and February is 

 the best month in whkh to spray. (Bui. 80, Part VIII., B. E. U. 

 S. Dept. of Agr.) 



INSECTS AFFECTING THE PLUM. 



The Plum Curculio. The small, crescent-shaped punctures so 

 commonly found on plums and other stone fruits in orchards east of 

 the Rocky Mountains are made by a small snout-beetle of rough 

 sculpture, known as the plum curculio. These bettles issue from their 

 winter quarters about the time the trees are in bloom, and feed on 

 the tender foliage, buds, and blossoms. Later they attack the newly 

 set fruit, cutting small circular holes through the skin in feeding, 

 while the females, in the operation of egg laying, make the crescentic 

 cuts so characteristic of this species. The egg, deposited under the 

 skin of the fruit, soon hatches into a very small whitish larva or grub, 

 which makes its way into the flesh of the fruit. Here it feeds greed- 

 ily and grows rapidly, becoming, in the course of a fortnight, the 

 fat, dirty white worm so well known among fruit growers. 



To be reasonably effective in killing the beetles, arsenate of lead 

 should be used at the rate of 2 pounds to 50 gallons of water. Paris 

 green or green arsenoid should not, on stone fruits, be used stronger 

 than 1 pound to 150 or 200 gallons of water. (Cir. 73, U. S. Dep. 

 of Ag., B. of E.; Bui. 25 Indiana Agr. Exp. Sta.) 



The Peach Tree Borer : See pages 54, 55, and 57. 



The Plum Slug (The Pear Slug) : See pages 47 and 

 58. 



The San Jose Scale: See page 32. 



The Plum Gouger. The gouger is a small snout-beetle, about 

 a quarter of an inch long. Its method of work is much like that of 

 the curculio. It is mottled brown in color, with short whitish hairs 

 that give it a pruinose appearance. It can be easily distinguished 

 from the curculio by its size and by the absence of humps on the 

 wing-covers. It confines its work for the most part to the Mississippi 

 valley and the West. 



The adult beetle hibernates in the winter, and in the spring at- 

 tacks the flowers of the plum in a manner at once peculiar and in- 

 genious. The part eaten is the ovule or the part which would, if 

 uninjured, in time become a fruit. The gouger eats a hole in the 

 side of the calyx, the green cup at the base of the flower, and reach- 

 ing in with its long beak eats the coveted part. Later the gouger 

 eats holes in the young fruit, sometimes laying eggs therein. The 

 egg is laid in a hole in the fruit with no crescentic flap as in the 

 case of the curculio. The young grub works directly into the soft 

 pit, and lives there, leaving no indication of its presence, except per- 



