The Orchids of the Benelux deals with the orchids of the Netherlands, Belgium and the Grand Duchy of Luxembourg in one edition. This reflects the clear correlation between these three countries through cross-border phytogeographical districts with their associated orchid species. For example, the calcareous soils in South Limburg which continue into Wallonia (The Calestienne)are characterized by their great numbers of orchids in both countries. These cross-border areas actually form larger coherent nature reserves where many of the same species occur.
This work covers all orchid species recorded in Benelux, including those which are now extinct there. These are presented logically in alphabetical order and described and discussed in detail. In addition, the most important subspecies and varieties are also described and discussed in detail. The taxa are presented with their correct nomenclature, type, basionym, characteristics, flowering time, habitat and ecology, as well as their overall distribution. The distribution in the Netherlands, Belgium and Luxembourg is also discussed separately by country with their historical and current information. All of the species are illustrated with many pictures of the plants and their habitats, as well as all of their hybrids recorded in Benelux . In addition, for each main taxon is there is presented a watercolour illustration, herbarium sheets of extinct species for each country, as well as historical and current distribution maps with a grid size of 4 km2 for three periods (1850-1950, 1951-1999, 2000-2018). The data is based on information obtained from various nature management institutes in the Benelux. Aligning the different grid systems from these three countries was very complicated, but with advanced software this problem could be solved.
In the Introduction, the systematics and biology, ecology and life cycle of the orchids in the Benelux are discussed in depth. Furthermore, some chapters deal with reintroduction and neophytes, protection and legal provisions, deterioration and threat, orchid-rich landscapes and habitats, as well as phytogeographical districts and information about the distribution maps. In addition, taxonomic aspects are also discussed, including the concept of species and other nomenclatural ranks.