SynopsisThe occurrence of ectomycorrhizal fungi in West African rain forest systems is demonstrated and linked to the presence of a range of caesalpinoid legumes and to members of the genus Uapaca. The vast array of boletes, members of the Russulaceae and Amanitaceae, and chanterelles is described. The virtual absence of ectomycorrhizal Cortinariaceae is emphasised. After an overview three separate yet interlinked studies are described: a survey of ectomycorrhizal fungi throughout the region (Thoen): ectomycorrhizal fungi of a single rain forest community (Watling) and the significance and relationships of the genus Russula in the Guinea–Congo Region (Buyck). Some comparisons are made with other rain forest areas of the world.

Summary1. In Europe, intensively managed coniferous plantations rarely achieve similar nature conservation functions as deciduous woodlands. The ability to identify coniferous plantations that might be successfully converted to deciduous woodland is a key goal in forest management. The herbaceous plant community composition of mature plantations may be an accurate selection criterion for stands that are most suitable for initiating the conversion process to deciduous forest. 2. The herbaceous plant communities in Norway spruce plantations were analysed using a functional group approach. The analysis was conducted in three steps: (i) identification of emergent groups (EG) by multivariate classification; (ii) comparison of EG abundance between coniferous and deciduous stands (i.e. the target communities); (iii) partitioning the variation in EG abundance in coniferous plantations between forest management, local environmental and regional variables. 3. Seven EG were identified: two core forest groups (short geophytes and zoochoreous perennials), two groups from open habitats (annuals and helophytes) and three mixed groups (anemochoreous perennials, graminoids and short perennials). 4. Among the core forest groups, short geophytes were severely under-represented in plantations (because of their low dispersal abilities and specific habitat requirements) while zoochoreous perennials were slightly more abundant (because of their good dispersal and competitive abilities). 5. Regional variables largely influenced the abundance of core-forest EG. Restoration of communities rich in zoochoreous perennials is far easier than restoring short geophyterich communities because of the different colonization abilities of these EG. 6. Forest management variables were of secondary importance for the restoration potential of plantations. Because generalist EG were favoured by low stand densities, forest practitioners should avoid large thinning operations. 7. Local environmental variables played a minor role in determining EG abundance. However, short geophytes preferred rather high soil pH values and were therefore negatively affected by acidification caused by coniferous litter. 8. Synthesis and applications. The performance of short geophytes is the key to conversion success of Norway spruce plantations to deciduous forest. Stands located on base-rich soils and in landscapes with high forest connectivity are the most appropriate candidates for initiating the conversion process. For other types of stands, future work should explore the possibility of restoring other land-use types, such as annually mown meadows.

Summary Ectomycorrhizas and ectomycorrhizal fungi of Afzelia africana Sm. and Uapaca guineensis Müll. Arg. are reported in forests of southern Senegal. Ectomycorrhizas occurred in dry and wet conditions, at different soil contents of available phosphorus (0–17.5 μg g−1). U. guineensis was confined to groundwater forests. Individual trees had both ecto‐ and endomycorrhizas, A. africana grew scattered in semi‐evergreen and riverside forests, whereas in the woodland it formed larger patches and could dominate the canopy. Eighteen putative ectomycorrhizal fungi grew under U. guineensis and thirty‐one under A. africana. Only six species were common to both trees, indicating an ecological and/or taxonomical selection. The fungi belonged to the following Orders: Russulales (16), Boletales (11), Agaricales (9), Cantharellales (2), Selerodermatales (2), Hymenogastrales (1), Gautieriales (1), Aphyllophorales (11). Some of them had a wide Sudano‐Zamhezian or Guineo‐Congolian distribution and reached their northern limit in Senegal.

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Use of the Australian genusEucalyptusin short rotation plantations in Africa and Madagascar has developed over the last century to such an extent that it is becoming the most frequently planted genus in Africa. In order to find ecologically well-adapted eucalypts, foresters have tested different species of various origins and the number of testedEucalyptusspecies now exceeds 150 in Africa. Due to the ability of eucalypts to naturally form ectomycorrhizae, even in the absence of any controlled introduction of compatible ectomycorrhizal fungal partners, their introduction in new ecosystems has direct consequences for ectomycorrhizal fungus communities. A bibliographical compilation, together with original field observations on putative ectomycorrhizal fungi associated with eucalypts in Africa and in Madagascar, has been drawn up in two lists: one for Africa and one for Madagascar where surprisingly high fungal diversity was observed. The level of diversity, the putative origin of the fungi, and their potential impact on native ectomycorrhizal fungi are discussed. The development of eucalypts plantations will inexorably lead to the increase of exotic fungal species being potentially invasive in the considered region.