24 CIRCULAR 16 8, U. S. DEPARTMENT OF AGRICULTURE 



of the first appearing in May, those of the second in late June, and 

 those of the third in July and August. The larvae are gregarious 

 in habit. The egg, larval, and pupal stages cover from 10 to 17, 11 

 to 12, and 6 to 12 days, respectively. Spraying with soap solution 

 containing pyrethrum powder during the early larval stages is rec- 

 ommended for control. 



Apriona rugicoWs (95, 188) at times attacks apple and pear trees 

 quite extensively, causing considerable damage, and occurs also upon 

 mulberry and fig, upon which hosts it is found even more commonly 

 than on apple. The life cycle extends over a period of three years, 

 and the adult beetles appear in the field during August. The eggs 

 are laid in groups of seven or eight in incisions in the bark of the 

 trunk and larger branches. The first-stage larva feeds in the cam- 

 bium layer, and the later stages in the woody portions of the tree. 



Chreonoma fortunei (95) has one brood each year upon apple in 

 Japan and hibernates in the mature larval stage in its burrow in the 

 wood. The adults appear in May or June. 



Oberea japonic® (150) is recorded as a serious pest of apple and 

 pear throughout Japan, Chosen, and Siberia. There is one genera- 

 tion a year. The egg is laid in an incision in the twig, and the j^oung 

 larva bores through the pith. Extensive damage is clone in some 

 sections. According to Takahashi (18S), the injury attributed to 

 this species is in reality caused by Apriona rugicoUis. 



The bupresticl beetle Agrilus mali (£, 106) is known as a pest of 

 apple in the central and northern sections of Chosen and occurs also 

 in Manchuria and China. The species has been studied by Mura- 

 matsu, who reports it to be very injurious in some sections, for at 

 times entire orchards of young trees have been killed, the branches of 

 the older trees being also injured. The adults are found in the field 

 from the middle of June until September. The eggs are laid singly 

 upon the surface of the bark of injured or < diseased areas or in 

 crevices in buds, etc. The larvae feed upon and tunnel through the 

 bark, but enter the woody portion to pupate. The bark of the 

 infested areas becomes blackened and dry, and a small quantity of 

 sap usually flows from some point of the injured area. The winter 

 is passed in the larval stage in the burrows in the bark. The egg, 

 larval, and pupal stages cover from 2 to 3 weeks, 10y 2 months, and 

 12 to 19 days, respectively. Control measures suggested are the 

 shaking of the adults from the tree into pans of oil, the cutting away 

 and burning of infested parts of the branches and trunk, and the 

 killing of the larvae in their burrows by the use of a broad-tipped 

 stick bearing many sharp-pointed nails, these being driven into the 

 bark where the larvae are noted to be present. 



Three species of Scolytidae (95, 122, 123) are recorded as found 

 upon apple in northern Japan; these are Cryphalus malus, Xyle- 

 borus apicalis, and Scolytus japonicus. The first also attacks cherry, 

 but in most cases injury is done only to trees which are deficient in 

 sap, and consequently not growing well. There is one generation 

 a year, the winter being passed in the adult stage in crevices in the 

 trunk and other sheltered places. X. apicalis hibernates in the 

 mature larval stage in the burrow. These burrows extend into the 



