Chrysophtharta bimaculata is a serious pest of eucalypt forests in Tasmania. The beetle overwinters as a diapausing adult, but it is poorly documented whether it forms overwintering aggregations or where it shelters. During winter 1992, we searched 386 possible overwintering sites for C. bimaculata in Eucalyptus obliqua forests. Fourteen types of habitat were identified, of which clumps of Gahnia grandis sheltered the greatest mean number of insects (3.31 ± 0.72 insects/plant, n = 65 plants), while bracken fern litter sheltered the least (0.14 ± 0.14 insects/sample, n = 7, 1 m 2 quadrat samples). Of the 14 habitat types, all except two (under the bark of eucalypt stags and in G. grandis clumps) were more often unoccupied. Beetles were more commonly found on mature forest edges or in logged and regenerating forests; few were found within mature forests. Our results show that C. bimaculata rarely forms overwintering aggregations of greater than 20 individuals per site, nor does it appear to have a significant pre-diapause dispersal.

Item Type:	Refereed Article
Research Division:	Agricultural, Veterinary and Food Sciences
Research Group:	Forestry sciences
Research Field:	Forest health and pathology
Objective Division:	Plant Production and Plant Primary Products
Objective Group:	Forestry
Objective Field:	Softwood plantations
UTAS Author:	Clarke, AR (Dr Clarke)
UTAS Author:	Shohet, D (Mr Shohet)
UTAS Author:	Patel, VS (Mr Vinu Patel)
UTAS Author:	Madden, JL (Dr John Madden)
ID Code:	13213
Year Published:	1998
Web of Science® Times Cited:	4
Deposited By:	CRC for Forestry
Deposited On:	1998-08-01
Last Modified:	2011-08-08
Downloads:	0