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



Xylotrechus chinensis (95) at times causes serious injury to mul- 

 berry in Japan by the boring of the larvae in the trunk and larger 

 branches. A single brood is produced each year, the adults appear- 

 ing in midsummer. The eggs are deposited in August and Septem- 

 ber and hatch in approximately two weeks. The young larva bores 

 into the cambium layer and there passes the winter. In the spring, 

 as growth proceeds, the woody portion of the tree is penetrated. 



Another species of this family, Aprionm rugicollis, is a serious pest 

 of mulberry, and a short account of it is given on page 2-i among the 

 insects attacking apple and pear. 



The bostrichid beetle Sinoxylon japonicum (Jf9) was first observed 

 as a pest of mulberry in 1918, when considerable damage was done 

 in Nagano Prefecture. Late in the spring the adult bores beneath 

 a bud and continues its burrow about 1 inch down the stem. The 

 affected buds die, and the twigs often break at the point of injury. 

 Nothing is known regarding the early stages. Persimmon and oak 

 are also chosen as host plants. 



The curculionid Bams deplanata (95) is at times a. serious pest 

 owing to its attack upon the new buds and twigs. The female beetle 

 chews a series of holes in a 3 T oung twig, and the eggs are deposited 

 therein. The larvae bore their way down through the woody por- 

 tion of the twig, ultimately killing it, and pass the winter in the 

 pupal stage in the burrow. In the spring the emerging adults feed 

 upon the buds and new leaves. 



The cecidomyiid DipJosis momvoreJJa (120, 201), is very common 

 in all sections of Japan where the mulberry is grown. The adults 

 appear in June and July, and the eggs are laid in the buds, from 2 

 to 20 being placed in each. The larvae cause the formation of 

 greenish-colored, plum-shaped galls from 5 to 9 millimeters in 

 length at the base of the new buds or on the stalks of the basal 

 leaves of young shoots. Infested buds often fail to develop. The 

 winter is passed in the larval stage in the fall, and pupation takes 

 ploce in early June in the same position. The injury inflicted by 

 this species is not so severe as might be, owing to the fact that the 

 basal rather than the terminal buds are attacked. The general 

 effect is an increase in the number, but a reduction in the size, 

 of the leaves produced, a disadvantage where the foliage is used for 

 feeding silkworms. 



Another species of this group known to attack mulberry in Japan 

 and Chosen is DipJosis quadr'ifasciata (10), which was previously 

 known only in the section about Tokyo, but is now a serious pest in 

 Chosen also. Two broods are produced annually, the adults of 

 which appear in May and July, respectively. The winter is passed 

 in the larval stage. Oviposition takes place upon fresh, soft shoots 

 which are in contact with the ground. The larvae bore under the 

 bark and eventually enter the cambium, causing these branches 

 to decay and eventually die. Damp places are very much preferred 

 as places in which to develop, consequently the branches near the 

 ground are much more heavily infested. The attack by these larvae 

 in numbers causes the bark to split, and it is in the crevices thus pro- 

 duced that the eggs of the second brood are usually placed. Protec- 

 tion may be obtained by pruning away all branches to at least 5 

 inches above the ground. 



