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during the summer, will greatly assist in checking this pest. If an 

 outbreak should occur, the seed-bed should be ploughed deeply as 

 soon as the plants have been set in the field. In regions where the 

 pest is serious, cabbage plants for spring setting should be grown 

 imder cheese-cloth screens. Murgantia histrionica, Hahn. (harlequin 

 cabbage bug) infests young kale during August and September. 

 While a few individuals may be found throughout the winter, many 

 bugs hibernate during January and February. The first and second 

 generations feed chiefly on wild mustard. Kale should be planted as 

 late as possible ; if early kale is required, one or two rows planted on 

 each side of the field about three weeks in advance of the regular 

 planting will attract the insects, which can then be destroyed by 

 spraying with pure kerosene oil ; or 65 to 75 per cent, of the nymphs 

 and 40 to 50 per cent, of the adults can be killed with a spray consisting 

 of 6| oz. nicotine-sulphate and 8 lb. fish-oil soap to 50 U.S. gals, water ; 

 this should be applied under a pressure of 175 to 200 lb. RlioixdosijThum 

 persicae, Sulz. (spinach aphis) is an omnivorous feeder, attacking 

 spinach, cabbage, egg-plants and many garden crops. The contact 

 sprays used for cabbage and potato Aphids are recommended against it. 



Cucumbers, cantaloups, squash and melons are attacked by 

 Diabrotica vittata, F. (striped cucumber beetle), which sometimes 

 entirely destroys the first plantings, or injures the blossoms sufficiently 

 to prevent the setting of the fruit. When only a few plants are grown, 

 they should be protected by cheese-cloth netting until the vines begin 

 to form. For field-crops, liberal applications of fish-scrap fertiliser 

 when the first seedlings appear act as a deterrent to the beetles 

 and stimulate the growth of the crop. Sprapng has not given good 

 results, as the insects avoid the poisoned leaves and attack only the 

 new growth. Calcium arsenate seems to have no effect on the beetles, 

 but further experiments are necessary with this substance. Heavy 

 applications of air-slaked hme, tobacco dust or sulphur on the young 

 plants are of decided value in preventing insect attacks. Seeds should 

 be sown thickly and, after danger from this insect is past, they may 

 be thinned to the required distance. Some species of StnyntJmrus 

 (springtails) attack cucurbits, S. liortensis. Fitch, being commonly 

 found on cucumber seedlings. Deterrents, such as tobacco dust, fish- 

 scrap fertihser and air-slaked lime are the most successful remedy. 

 These should be applied liberally when the plants begin to appear 

 above ground and again about one week later. Diabrotica duodecim- 

 punctata, Ohv. (southern corn root worm) should be dealt with by 

 the same methods as those advocated for D. vittata. Aphis gosstjpii 

 (melon aphis) feeds on the under-side of cucurbit leaves, causing them 

 to curl and die. The insects are first found abundantly on a few plants 

 only, and these should be sprayed with 6| oz. nicotine sulphate 40%, 

 and 4 lb. fish-oil soap to 50 U.S. gals, water. Anasa tristis, DeG-. 

 (squash bug), is troublesome in the nymphal stage and can then be 

 killed by spraying with 1 lb. soap to 6 gals, water containing 1 oz. 

 40% nicotine sulphate. Where possible, the conspicuous brown eggs 

 laid on the leaves should be destroyed, and adults may be attracted 

 to the shelter of stones or boards placed near the plants, where they 

 can be destroyed in the morning. Melittia satyr inif or 'mis, Hbn. 

 (squash vine borer) is one of the most serious pests of squash and 

 pumpkins. The larvae bore into the base of the stem, causing wilting 



(C416) D 



