34 



THE EEDWOOD. 



until their legs and wings are full}' developed, when, as full}' matured 

 adults, they bore their way. out through the wood and bark, producing 

 the shot-hole condition, as shown in the illustration. 



It is known that the xvedwood bark-beetle tiies early in April and 

 attacks the living bark of recently-felled trees, but as. yet we have no 

 positive evidence that it attacks standing living trees. The fact, how- 

 ever, that a near relative, the Lawson\s Cypress bark-beetle, will 

 attack and kill trees, indicates that under specialty favorable conditions 

 this species may do likewise. Therefore any 

 unhealthy condition of the 3"oung or old trees 

 in which the leaves toward the top turn yellow 

 and reddish brown should be examined for 

 traces of the beetle's work in the bark and at 

 the base of living twigs. 



EEMEDT. 



If it should be found that this beetle is at- 

 tacking living trees, its known habit of infest- 

 ing recentty-felled trees suggests that it might 

 Jig. 1.— The Redwood bark easily be controlled b}' Cutting and barking all 

 beetle: aduu-eniarged(orig- infested trees between the 1st of September 

 and the 1st of Decenaber, and by providing a few 

 trap trees to attract those beetles that escape. This maj^ be accom- 

 plished b}" felling a few trees in December: Then after the adults 

 have entered the bark in the spring and the larvte (grubs) are about 

 half -grown, or before thej enter the surface of the wood, if the bark 

 is stripped from all the infested parts of the trunk and larger branches, 

 the broods will be destroyed. It will not be necessary to burn the 

 bark thus removed, because the drying of the inner surface will kill 

 the- young stages, while some of the natural enemies of the beetle 

 which wou-ld otherwise be destroj^ed b}^ burning might survive to be 

 of service in reducing the numbers of those which are not attracted to 

 the trap trees or which breed in the standing timber. The tops and 

 smaller branches, which can not conveniently l)e barked, should be 

 burned, but they should first be left until the broods are nearly devel- 

 oped, in order that the parasites and other natural enemies maj^ has'e 

 time to develop and emerge to continue their good work. It would 

 be best if this material were burned just before the beetles begin to 

 emerge. 



The life history" of the Redwood bark-beetle has not been worked out, 

 but the insect is probabl}' double-brooded, the first brood emerging 

 about the middle of summer and the other the following spring. If 

 this is true, it is of the greatest importance to protect, so far as pos- 

 sible, the natural enemies of the first brood, in order that they may 

 continue their depredations on. the second brood. 



