Cambio-xylofauna abundance and species diversity of cutting residues in Scots pine and Norway spruce clear-cuts in Lithuania

The research was conducted at Dubrava Training Experimental Forest Enterprise, Kaunas District, Lithuania, in 2004. The aim was to estimate the abundance, species composition and diversity of cambio-xylofauna hibernating in oak, Norway spruce and Scots pine cutting residues (branches) left in spruce and pine clear-cuts. The research plots with replicates were arranged in the clear-cuts from September 2003. More than 1000 arthropods were identified in oak, spruce and pine cutting residues. The class of Insecta was represented by the orders Diptera (51%), Psocoptera (24%), Coleoptera (22%) and Hymenoptera (2%). According to the Shannon diversity index, species diversity of cambio-xylofauna hibernating in thin spruce branches (H=2.19) was significantly (p=0.001) higher than in spruce branches of medium diameter (H=1.36). The difference between species diversity in thin and thick spruce branches was unreliable (p=0.2). In oak cutting residues (branches), 7 rare (Bitoma crenata Fabr., Dissoleucas niveirostris, Fabr., Leiopus nebulosus L., Pyrochroa coccinea L., Saperda scalaris L., Sulcacis affinis Gyll., Trachodes hispidus L.) and 3 very rare (Cis hispidus Gyll., Mordella aculeata, L., Orthocis alni Gyll.) insect species, as well as 1 species new in Lithuania (Phymatodes alni L.), were identified.