Reassessment of lyctine susceptible sapwood
This study examined the lyctine susceptibility of 16 timber species or hybrids. Several of the timbers have previously been placed in a ‘rarely susceptible’ category, but for standards and compliance purposes, such in- between ratings are not acceptable. Timber samples were spot tested for starch content and exposed to three species of lyctine beetles—Lyctus brunneus, which is found Australia wide, and the smaller species L. discedens and Minthea rugicollis.
Lyctine susceptible species were: Erythrophleum chlorostachys (Cooktown ironwood), Eucalyptus delegatensis (Alpine ash-Tasmania), Eu. regnans/obliqua (ash/messmate), Corymbia nesophila (Melville Island bloodwood), Eu. fibrosa (Broad-leaved red ironbark), Eu. grandis (Rose gum), Eu. crebra (Narrow-leaved red ironbark), Eu. argophloia (Western white gum), Eu. dunnii (Dunn’s white gum), Eu. regnans (Mountain ash), Eu. saligna (Sydney blue gum), Eu. grandis/saligna hybrid.
Non-lyctine susceptible species were: Eu. cloeziana (Gympie messmate), Eu. delegatensis (Alpine ash- Victoria or NSW), Eu. pilularis (Blackbutt), Eu. sieberi (Silvertop ash), Eu. tetradonta (Darwin stringybark).