Most of these woodlands have now been replaced by ‘high


Most of these woodlands have now been replaced by ‘high

forests’ for timber production, or with modern agricultural lands. In Sweden, this decline of old trees is well documented for oak (Eliasson and Nilsson 2002). The ancient trees which remain until today were most often growing on land owned by the nobility, who could afford to keep them in parks or other semi-natural land. A century ago this land consisted of wooded meadows used for grazing, hay production and/or hunting. Today some of these areas are still kept open by grazing or they have regrown with young trees while the rest have been transformed to land without old trees. Land where the old trees still remain are highly prioritised in conservation work with protection and restoration. In Europe, parks were often established around manor houses in the late 1600s or in the 1700s. Avenues of trees selleck products were an important feature of parks, with lime (Tilia spp.) being the most popular species at that time (Bengtsson 2005; Sernander 1926). In most of these old parks,

at least in Sweden, some 300-year old trees still remain from the original plantings (Bengtsson 2005). A number of the original trees have died, but these have usually been individually replaced, so creating a continuous supply of trees that might grow into old age. As manor houses are relatively abundant in the countryside of the region where the present study was conducted, their parks probably harbour a considerable proportion of all the ancient trees present on a landscape-scale. The tree species studied in this paper is lime (Tilia spp.), which hosts fewer saproxylic beetle species than, e.g. oak (Palm 1959). Compared to most other deciduous tree species, however, lime has a comparatively large assemblage of specialised saproxylic beetle

species (Ehnström 2006; Palm 1959; Warren and Key 1991). But in general host specific differences in the fauna of ancient trees are not large because associated species are not usually confined to a single host species (Warren and Key 1991). Instead, the unique AZD1480 ic50 structures, such as hollows, dead parts of the trunk, dead branches, etc. are the important features. Because old lime oxyclozanide trees are so frequent in parks, they might constitute an important proportion of habitat available at a landscape-scale, and so contribute to the long-term persistence of populations of saproxylic beetles. The questions addressed in the present paper are: (1) Can park trees host a saproxylic beetle fauna as diverse as that found in trees of more natural stands?   (2) Is there a difference if the natural sites are open grazed or re-grown?   Materials and methods Study area The study was conducted in an area of about 100 × 120 km2 situated around and north of lake Mälaren in Sweden (16°00′′–18°00′′E and 59°20′′–60°20′′N) (Fig. 1). The area lies within the hemiboreal zone (Ahti et al.

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