The aim of this research was to study (1) the biodiversity and ecology of ectomycorrhizal fungi in a native pinewood (P. sylvestris) chronosequence, analyzing their possible successional trends in species richness, composition and relative abundance with stand age.  (2) The possible effects of organic and mineral soil depth.  (3) If these changes reflect changes in functional attributes of ectomycorrhizal (EcM) communities as represented in the proportion of different exploration types.  (4) To test their potential in vitro interactions with understorey ericaceous plants. Ectomycorrhizal communities were studied in a native pinewood from Glen Tanar Nature Reserve, northeast Scotland, UK. The overall species richness in Glen Tanar pinewood was 136 EcM taxa, this figure represent 68% of species previously known to occur associated with Pinus in Britain.  Sporome surveys reveals a rich epigeous and hypogenous EcM community with 70 identified taxa and 30 identified to genus, of which the dominant genus was Cortinarius. Below-ground surveys revealed an EcM community of 46 morphological groups recovered from 43116 pine roots, of which 95.8% were found in the organic horizon.  Cortinarius spp., Russula sardonia, Tomentellopsis submollis, Cadophora cf. finlandia, Russula paludosa, Suillus variegatus and Pseudotomentella tristis were the dominant species with 66% of the total roots recovered.  In vitro experiments between selected EcM fungi and four ericaceous plants revealed some degree of interactions, demonstrating for the first time the ability of a fungus from the Hymenoscyphus ericae aggregate (Cadophora cf.  finlandia) simultaneously to form both ectomycorrhizas with Pinus sylvestris and what appear to be ericoid mycorrhizas with Vaccinium myrtillus and V. macrocarpon.