National Herbarium the Netherlands

The NHN herbarium database has been built over the years for various purposes and from various sources. The majority of records relate to specimens present in one of the NHN herbaria (Leiden, Utrecht and Wageningen). The database also contains records of duplicates that have been sent to other herbaria, of materials databased for taxonomic revisions, and of specimens collected in areas of special interest for NHN (for instance Gabon) that were databased for that reason.

The three herbaria that form the NHN each have their own focus. Leiden is by far the largest of the three, with about 4 million specimens and well-known for its extensive collections from Southeast Asia, especially from Indonesia and New Guinea, but it also holds a large collection of palearctic plants, and is the principle herbarium for Dutch plants. As the oldest Dutch herbarium, it also contains several historic collections.

The former herbarium of Utrecht University, now housed in Leiden, has a strong focus on tropical America, especially the Guyanas and the Netherlands Antilles. It has around 800,000 specimens.

The herbarium of Wageningen University houses approximately 900,000 specimens. It focuses on tropical Africa, with particular emphasis on material from the rain forests of West and Central Africa, but it also holds an important collection of Ethiopian plants. Since Wageningen was originally an agricultural university, this collection also contains a fair number of cultivated plants