CONTROL OF THE JAPANESE BEETLE ON FRUIT AND SHADE TREES O 



in the spray. All portions of the plant should be covered with a 

 film of the spray deposit. (Fig. 4.) Any uncovered area on foliage 

 or fruit will be selected by the beetle for feeding. Since the beetle 

 first attacks the upper portions of the plant, it is essential that these 

 parts be well protected with a coat of spray. A much larger quan- 

 tity of spray is necessary for combating this pest than is ordinarily 

 employed by commercial fruit growers in the control of miscellane- 

 ous orchard pests in the vicinity of the original infestation. A 25- 

 year-old apple tree approximately 20 feet high with a branch spread 

 of 25 feet requires at least 18 to 20 gallons of spray solution evenly 

 distributed over the foliage and fruit. 



If any infestation of beetles is present or if the plant has already 

 been injured, the problem of preventing further injury is more dif- 

 ficult. Therefore, the importance of applying the sprays before in- 

 festation or injury occurs can not be overemphasized. Since beetles 

 will attract beetles, the secret of control is to apply the spray before 

 the beetles are present in large numbers. In a normal year sprays 

 should be applied by July 4. 



SPRAY MATERIALS 



Lead arsenate 1 plays an important part in the control of the Jap- 

 anese beetle. It is the best known and most extensively used stomach 

 poison for the destruction of insect life. It is comparatively safe to 

 use on all types of foliage, remains on the foliage longer than any 

 other stomach poison, mixes well with water, and on account of its 

 fineness remains well in suspension. Its greatest advantage, how- 

 ever, is its high repellency to the beetle when used at a strength of 

 6 pounds to 100 gallons of water. 



Ordinary wheat flour, averaging approximately 16 per cent gluten 

 content, is added to the lead arsenate to increase its power of adher- 

 ing to the plant. 



Lead oleate coated lead arsenate, which is recommended in this 

 circular particularly for shade trees and shrubs, is ordinary acid 

 lead arsenate paste, containing approximately 55 per cent water, 

 treated during manufacture with lead acetate and oleic acid to form 

 a 2 per cent lead oleate coating of the lead arsenate paste. The 

 spray was developed at the Japanese beetle laboratory during a search 

 for a toxic material which the beetle would eat readily. Not only 

 does the addition of the lead oleate increase the kill of beetles, but 

 the material possesses good adhesive qualities. 



Hydrated lime is a well-known commercial product made by slak- 

 ing stone lime with water, either as such or in the form of steam. 

 This should not be confused with a slaked lime. Where hydrated 

 lime is substituted for stone lime, one-fourth of a pound more should 

 be added for each pound of stone lime. 



Calcium casemate, a commercial mixture of casein and lime, has 

 been widely advertised as an effective spreader for certain insecti- 

 cides. 



New Jersey dry mix is a fungicidal spray combination composed 

 of finely ground sulphur and lime to which calcium casemate has been 



1 Unless otherwise specified, the term " lead arsenate " as used throughout this circular 

 refers to the dry form of acid lead arsenate. 



