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in southern Missouri and Arkansas. Recent outbreaks have originated 

 in fields of early sown wheat or in wheat which follows an oat crop, 

 there being a growth of self-sown oats present among the wheat. The 

 extent of the damage caused by this insect depends largely on the 

 weather conditions prior to the middle of April. If the temperature 

 is high enough to enable the Aphids to breed throughout the winter and 

 at the same time is too low for the development of their natural enemy, 

 the Braconid, Aphidius testaceipes, a serious outbreak over a large 

 area may be expected. In the more northern states T. graminum 

 passes the winter in the egg-stage, and the numbers are not likely to 

 increase sufficiently in the spring to cause serious injury. Areas 

 affected are recognised by the colour of the wheat changing from green 

 to yellow and should be ploughed deeply and then rolled. Self-sown 

 grain should, if possible, be destroyed by grazing in late autumn or 

 early winter, as this measure destroys the initial breeding grounds both 

 of this pest and of the Hessian fly, Mayetiola destructor. 



PoETEREN (N. van). Het Gebruik van Carbolineum bij de Bestrijding 

 van Schadelijke Dieren. [The use of Carbolineum for the control 

 of animal pests.] — Tidsch. Plantenziekten, Wageningcn, xxii, pt. 1, 

 January 1916, pp. 1-36. 



In the last three years the use of carbolineum for the control of 

 ^insect pests has greatly increased and the results have been good. 

 As a contact poison, it is economical in use and of wide application ; 

 there is also reason for hoping that it may prove useful against fungus 

 diseases. It has been tried and found useful as a spray for orchard 

 and bush fruit, though care must be exercised in the case of certain 

 kinds, such as peaches. Aphids, Coccids and the larvae of many 

 Lepidopterous and other pests are destroyed by it. It appears to be 

 an excellent general insecticide for flowers under glass, especially roses, 

 a 5 per cent, solution in water being sufficient for this purpose ; 

 Typhlocyba rosae is controlled by it. A list of 13 species of Abies and 

 20 of Picea is given, which were sprayed respectively with a 7| per cent, 

 and a 3 per cent, solution without harm to the trees and with apparently 

 good results. The common pest of azalea nurseries in Holland, 

 Phyllocoptes azaleae, can be controlled by a carbolineum spray. Against 

 Psylla huxi it may be used as a preventive, but it is not effective against 

 Monarthropalpus buxi or Phytomyza ilicis. It cannot be used against 

 white fly (Aleurodes) on Japanese azaleas, as the plants themselves 

 are damaged. Dressing the trunks with carbolineum solution will 

 prevent the growth of moss and lichen on trees, and it has proved a 

 very efficient dressing against canker when used in 25 or 50 per cent, 

 solutions. Generally speaking, plants will bear a much stronger 

 solution of carbolineum than is necessary to destroy the pests on them. 

 An 8 per cent, solution, if properly used, is sufficient for orchard trees 

 and bush fruit ; a 10 per cent, solution seems to be necessary against 

 Eriosoma lanigerum, but nothing stronger than 5 per cent, must be 

 used for peaches. It has been stated that carbolineum has a directly 

 beneficial effect upon the plants sprayed with it, but the author denies 

 this and considers that, though no harm is done, there is some evidence 

 of a retarding action on the growth in the spring, especially in the cas*^ 

 of species of Buxus. Conifers can only be sprayed late, at the end t 



