412 



soap 10 lb., petrol 1 gal., and water 10 gals. They can also be destroyed 

 by spraying with hot water at from 140° to 149° F., a treatment 

 which does not injm-e the trees. 



Good results have been obtained by filling up the crevices in the bark 

 in autumn with the follo^^dng mixture : — Rain-water 5 pints ; black 

 soap 35 oz. ; sodium sulphoricinate 5 oz. The base of the roots should 

 be watered with a mixture of rain-water 5 pints ; potassium carbonate 

 f oz. ; sodium sulphoricinate 3 oz. ; methylated spirit 2 oz. ; nicotine 

 (of standard strcDgth 2 oz. per pint) ] oz., the same liquid being also 

 suitable for use as a spring spray. 



Department of Entomology. — 43rd Ann. Rep. {1917), Ontario Agric. 

 Coll., Toronto, 1918, pp. 18-24. 



Insect pests were not markedly abundant during the year under 

 review, the severity of the previous winter and the late spring and 

 summer undoubtedly reducing the numbers of many species. 

 Contarinia (Diplosis) tritici (wheat midge) appeared in several new 

 counties. This midge oviposits when the ears are formed on the 

 growing grain, at the tip of the husk covering the soft kernel. The 

 larvae hatch in about a week, enter the grain and feed on the contents, 

 leaving only the husk. When full-grown, they descend to the ground, 

 pupate a few inches below the surface and remain dormant during 

 the winter. Many larvae remain in the heads after the grain is ripe 

 and are cut down with it. The maggots cannot be destroyed when 

 in the ear, and preventive measures are the only practicable course. 

 It is essential that all chaff and refuse from the threshing machine 

 be swept up and burnt immediately. If possible, the stubble in the 

 field should be burnt over and the field should be deeply ploughed 

 in order to bury the pupae too far for the flies to emerge in the following 

 year. After ploughing, the ground should be rolled and wheat should 

 not be sown on the same field for one or two seasons. The wheat known 

 as Red Fife is considered the most resistant to attacks by C. tritici. 



Datana iyitegermna (checkered tussock worm) defoliated walnut 

 and butter-nut trees. Schizitra concinna (red-humped caterpillar) 

 was abundant on fruit trees in many localities and should be shaken 

 of? the trees and destroyed. Ceramica (Mamestra) picta (zebra 

 caterpillar) was present in large numbers on cabbages, beets, turnips 

 and other vegetables. The best results were obtained by dusting 

 Avith Paris green diluted with about 30 parts air-slaked lime, hydrated 

 lime, or land-plaster (gypsum). The larvae of the moth, Depressaria 

 heracleana, caused much destruction to the flowers of parsnips, spinning 

 a web over them and devouring them and then boring into the stems. 

 All affected heads should be cut off and burned, and wnld parsnips 

 or other umbelliferous flowers in the vicinity should be cut down and 

 destroyed. 



In green-houses the larvae of the Pyralid, Pionea {Phlyctaenia) 

 ferrugalis, have been troublesome on chrysanthemums ; the fern 

 scale {Hemichionaspis aspidistrae) has also appeared in some conser- 

 vatories. Among household pests, Lepisma sp. (silver-fish) has been 

 found damaging wall-paper, the binding of books and some starchy 

 foods. Sodium fluoride proved successful against this pest and also 

 against cockroaches. 



