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as the eggs of the first generation begin to hatch, the treatment being 

 repeated as often as necessary. Epitrix mmmeris, Harr. (potato 

 flea beetle) has only recently appeared in Minnesota, but is found 

 to do considerable damage in limited areas and will probably become 

 an established pest. The larvae attack the roots and then burrow 

 into the tuber ; the adults feed on the imder-side of the leaves. There 

 is only one generation in a year. Bordeaux mixture has a repellent 

 effect upon the beetle, but must be applied to the under-side of the 

 leaves. Empoasca rnali, Le B. (apple leaf-hopper) attacks many 

 field crops, besides being an apple pest, and is particularly injurious 

 to potatoes, upon which it appears in late June, ovipositing on the 

 stems. It remains on the plants as long as they are green ; there are 

 two generations and perhaps a partial third. A contact spray, such 

 as Nicofume, used in the strength of | U.S. pint 40 per cent, extract 

 to 50 U.S. gals, water, with the addition of 2 lb. soft soap, shovdd be 

 used at the time when most of the hoppers are wingless, that is generally 

 before the middle of July. Macrosiphum solanifolii, Ashm. (potato 

 aphis) migrates to potato in late June or July, where it reproduces 

 rapidly until the autumn migration. Natural enemies include 

 Coccinellid beetles, Syrphid and lace-wing flies and various parasites. 

 A contact spray should be used as for the leaf-hoppers, when the 

 natural enemies are an insufficient check. Other potato insects 

 include Epicauta pennsylvanica, De G. (blister beetle), various plant 

 bugs, Phytometra (Autographa) brassicae, Riley (cabbage looper), 

 stalk borers, cutworms, white grubs and wireworms. General rules 

 for spraying potatoes are given. 



Pests of vegetables include cutworms, white grubs, Aphids, Lejytino- 

 tarsa decemlineata and Diabrolica vittafa, F. (striped cucumber beetle), 

 against which cucumber plants should be protected with cheesecloth 

 covers until well developed, and the larvae killed at the roots with 

 nicotine extract. Pieris {Pontia) rapae, Schr. (cabbage worm) should 

 be checked with lead arsenate powder dusted on the plants. 

 Phorhia {Pcrjomyia) brassicae, Bch., is a well-known pest of cabbage, 

 cauliflower, radishes, turnips, etc. ; tarred felt discs are required to 

 protect the stems of the plants from it. A poison- bait made of 

 f oz. lead arsenate, | U.S. pint molasses and 1 U.S. gal. water, is used 

 to kill the adults before they lay eggs. Peas and beans attacked by 

 Bruchids should'' be heated in an oven to 180° F. before being stored 

 in a dry place or in dry bins. General instructions for cultural methods 

 and the use of insecticides are given. 



Insects injurious to small fruits include Pteronus ribesii, Say 

 (imported currant worm), of which there are two generations, one in 

 early summer and the other about six weeks later. Poisons should be 

 applied either in dust or liquid form. When the fruit is ripening, 

 hellebore should be used ; for liquid sprays 10 teaspoonsful of lead 

 arsenate or 2 of Paris green should be used in 1 gal. of water. 

 Aegeria (Sesia) tipH.liJormis, Clerck (currant borer) in the larval stage 

 burrows in the stems of currant bushes, eventually killing them. All 

 injured stems should be pruned and burnt before 1st June. Myzus 

 rihis, L. (currant aphis), can be controlled by a contact spray of 

 1 or 2 tablespoonsful of Nicofume in a U.S. gal. of water, with a little 

 soap. Agrilus rufcollis, F. (red-necked cane-borer) burrows spirally 

 round raspberry canes, causing gall-like swellings and finally killing 



(C496) a2 



