When a new species of plant is discovered and named, a representative specimen, the “holotype”, is deposited in a registered herbarium, or plant museum. It has now become known to science. New specimens, when collected, are compared with the existing holotypes and technical descriptions, and are identified or named accordingly. The publication of national “floras”, or detailed inventories of all the species discovered in a country (such as The Flora of Thailand), greatly aids in the identification of plant species. The inventory and naming of all plant species will never be complete, however, because the discovery of new plants, and the use of newer methods of classification—especially the use of DNA analysis—call for the frequent revision of names and classifications of species. The use of DNA sequencing is an aid to—not a replacement of—traditional methods of classification. The DNA sequence of the genome of a species is meaningless without reference to physical specimens in an herbarium. An herbarium specimen usually consists of leaves, flowers and fruits of the species pressed, dried, and mounted on sheets of stiff paper, and stored in cabinets arranged according to plant family and genus. Attached to each sheet is a label giving all the pertinent information about the specimen.
BIOTEC has established an herbarium (officially designated as herbarium BBH), now managed jointly by BIOTEC and NBT, mainly for storing specimens of interest to researchers at NSTDA. It is divided into two sections: a fungal section, and a vascular plant section. The vascular plant collection houses all specimens from the Mo Singto plot and will also include all species stored in the seed bank. This collection includes holotypes of two new species of trees discovered on the Mo Singto plot. Herbaria also commonly store voucher specimens for “ecological inventories” which document all the species occurring in a particular location (such as a research plot, or a whole conservation area). Herbaria such as BBH are vitally important to conservation efforts because they document the geographic ranges of species in the past, for comparison to more recent, and future information