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HoDGKiss (H. E.). Control of Green Apple Aphis in Bearing Orchards. 



—New York Agric. Expt. Sta., Geneva, N.Y., Bull. 461, June 

 1919, pp. 97-134, 10 plates. [Received 20th November 1919.] 



The author's conclusions are as follows :— The green apple aphis 

 [AiiMs pomi] lives on apple trees throughout the year. On ac<;ount 

 of a late spring migration of winged forms and the later breeding of 

 the insect, the pest is difficult to control by a single spraying in the 

 season. If control measures are unduly delayed the insect's activities 

 may result in severe injuries, such as curling of leaves or deforming of 

 fruits. Curled foliage and the stems of fruits, as well as the clusters 

 of apples, afford hiding places for the Aphids, which are difficult to 

 reach with the spraying mixture unless it is applied generously and 

 with considerable force. Applications of coarse sprays in liberal 

 quantities are necessary to wet the leaves and the insects thoroughly. 

 Such treatments often reach Aphids that escape mist sprays, and by 

 thorough and timely spraying the summer broods can be controlled 

 even on trees of considerable size. The delayed dormant spray, by 

 protecting the trees from early infestations, diminishes the oppor- 

 tunities for serious reinfestations from the late spring migrations. 

 A nicotine sulphate and soap spray is a very satisfactory aphidicide 

 on account of its rapidity in killing, ease of application, and its spread- 

 ing and adhesive properties. 



Nicotine sulphate and lime is especially advantageous on trees of 

 medium size with large amounts of succulent growiih, because' of its 

 deterrent influence on the insects in addition to its immediate 

 killing properties. In plaiming spraying operations against 

 the green apple aphis, chief dependence should be placed on the 

 nicotine sulphate-soap spray for trees of unusual height. With plant- 

 ings of younger trees or those newly set, especially where succulent 

 fc,tems are likely to be seriously injured, an application of nicotine 

 sulphate and lime will prove an efficient and satisfactory treatment. 



The following formulae are given for the above sprays. 



Nicotine sulphate-soap solution :— Nicotine sulphate (Blackleaf 40) 

 I U.S. pint (1 pint in severe attacks) and soap 4 lb, to 100 U.S. 

 gals, water. 



Nicotine sulphate- lime wash :— Stone or hydratei lime 60 lb., 

 copper sulphate 2-4 lb. and nicotine sulphate | U.S. pint (1 pint hi 

 severe attacks) to 100 U.S. gals, water. 



WoGLUM (R. S.). U.S. Bur. Entom. A Dosage Schedule for Citrus 

 Fumigation with liquid Hydrocyanic Acid.— JZ. Econ. Entotn. 

 Concord, N.H. xii, no. 5, October 1919, pp. 357-363. 

 Further experiments have been made with regard to the comparative 

 efficacy of liquid hydrocyanic acid and pot-generated gas which 

 confirm previous observations [R.A.E., A. vii, 228]. The present 

 experiments were conducted chiefly against black scale [Saissetia oleae], 

 purple scale [Lepidosafhes beckii] and red scale [Chrysomphcdus aurantii]. 

 A dosage schedule based on field experience is given according to which 

 the smaU trees are practically dosed in proportion to their cubic con- 

 tents, whereas larger ones approximate to the ratio of surface area of a 

 domeshaped figure to its cubic content. The experiments against 

 Lepidosaphes beckii with liquid hydrocyanic acid at the rate of 16-56 

 c.c. as equivalent to 1 ounce of sodium cyanide show better results 



