354 



YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 



not to be immediately sawed into lumber, is to remove the bark imme- 

 diately upon felling or betAveen the 1st of March and 1st of June. 

 Placing the logs in water after the larvae have hatched and before 

 they have entered the wood is also effective. 



THE RED-HEADED CLYTUS. 



crythroceplialus Fab.) 



The red-headed clytus is a close relative of the banded ash borer 

 and does considerable damage to the wood of dead and dying ash, as 



well as to a number of other trees. The 

 list of its host plants includes ash, horn- 

 beam, hickory, maple, sweet gum, chest- 

 nut, cypress, hackberry, black walnut. 

 dogwood, black oak. persimmon, peach, 

 locust, sassafras, holly, mesquite, Texas 

 redbud, pine, Kentuck}^ coffee tree. 

 lilac, honeysuckle, and grapevine. 



The larva is a slender, white, footless 

 grub of varying length when mature. 

 the average length at this stage being, 

 perhaps, about 15 mm. The adult is ti 

 slender beetle, 6 to 16 mm. in length. 

 The head and prothorax are red. The 

 anterior part of the elytra is reddish, 

 shading into dark brown or black pos- 

 teriorly. The elytra bear four pairs of 

 yellow bands, the first pair being at the 

 extreme base. There is but one genera- 

 tion a year. It appears that eggs may 

 be laid anywhere from March to Sep- 

 tember. The adult female deposits the 

 egg in a crevice of bark on a dead or 

 dying tree or log. The young larva, 

 hatching from the egg, mines first in the 



inner bark and later continues the mine in the sapwood, thus injuring 

 the wood for commercial purposes (fig. 27). Pupation takes place 

 in the sapwood. The adult emerges from the tree or log the follow- 

 ing spring or summer after the egg is laid. This species is common 

 from the District of Columbia to Ohio, and south to Texas. 



The same preventive measures as those given for the banded ash 

 borer apply to this species except, it will be noted, that the egg-laying 

 period of this species is much longer than that of the banded ash 



FIG. 27. Work of the red-headed 

 clytus (Xeuclytus ei'i/tlircxepha- 

 1ns) Sections of hickory log 

 showing : a, Larval mines on sur- 

 face of wood ; 6, larval mines in 

 the wood ; c, entrance hole of 

 larva into wood. (Original.) 



