Insects Emerging from Prepared Timber In Buildings

G Spencer
Several insta nces ha ve come to m y a ttentio n, in the last four yea r s, of beetles emerging from Aoo rs a nd walls of woode n buildi ngs in this Province. I am awa re that mention of this type of e mergence has been m ade in lite ra ture , but the o nl y r ecord I ca n loca t e in the scanty literature avai lab le to m e, is in Gra ham's "Principles of Forest Entomology," in which he refers to beetles emerging fro m furniture t wenty yea rs af ter it was manufactured. U nfo rtunate ly, he
more » ... fo rtunate ly, he is no t specific as to the specie s of beetle a nd of the wood concerned, a nd he g ives no r efe re nces. In the insta nces under co nsideration a t th e mo ment, beetles of the Fa mil y Buprestidae a r e chieAy concerned; one is of the family Ceramby-cidae. Of the li fe-hist o ry habits of the Bupres tid ae, Stebbing, in hi s "Indian Forest Insects," g'ives the fu ll est accounts I can find of seve r a l specie s of several gene r a. A typical li fe-histo r y, as he represe nts it, is as fo ll ows :-the female beetles, moving mostly in bright sunlight, ovi-pos it in cracks and crevi ces of the ba rk a nd the la rv ae ha t ching fr om the eggs tunne l th rough the bark t o the bast, whe reo n the y feed. So me feed principa lly in th e bast o r in the can. bi um where they sculpture the surface of the wood a nd then enter the sap-wood, o r else wo rk down di r ectly into the sap-wood, where they co mpl ete the la tte r stages of la rva l g row th. In these tunne ls of larva l development, sawdust of chisel-lings and frass is ti ghtly packed. The mature la rv a just before pupating, li ves in a tunne l fr ee from sawdust. I-Iav ing cut a passageway to nearly the surface o f the w ood, the la r va pupa tes in th e burrow. Rarely does Stebbing menti on a larva ente ring the hea rtwood; most feed in the bast and th ose of ge nus Chrysobothris in the cambi um. H. E. Burke, of the U nited States Depa rtm ent of Agri culture, states that (1917) "Eggs (of the Buprestidae) a re deposited by th e mothe r sing ly o r in a mass o n the bark or a re tu cked in so me cr evice in the bark o r w ood o r und e r t he ba rk at the edge of some wo und. Each la rv a mines th e inne r bark o r wood until it reaches m a turity." Essig, of California, mentions th a t the la rv ae o f ge nus Chrysobothris feed on th e cambium to the sap-wood and down to th e he a rt-wood but most la r vae o f the fami ly wo rk in the sap-wood. He mentio ns only o ne beetle, Buprestis gibbsi Lee, as mining straight dow n to th e heartwood-and Leng does not record this species fo r this Pro vince. The co nse nsus of opinion seem s t o be that the la rvae o f a ll species feed for aw hile in th e bark or bast o r ca mbium a nd either co mplete the ir growth the r e or barely enter the sap-wood, o r enter the sap-wood