Oakes Ames, G. L. Goodale's successor in the Botanical Museum, took a particular interest in developing two special collections: an orchid herbarium (AMES) and a collection of plants of economic importance (ECON).  

The orchid herbarium is exceptionally rich in type specimens, with nearly 2,500 holotypes (including nearly 800 described by Ames) and 3,500 isotypes. An exceptionally important collection of type specimens and drawings of types was received from Rudolf Schlechter and Rudolf Mansfeld of the Berlin-Dahlem herbarium (B). Schlechter and Mansfeld's specimens were destroyed during the bombing of Berlin in the 1940's. Hence, our holdings represent the only remaining documentation for many of the species described by these two botanists. Another important collection comprises an extensive and unique set of drawings and types designated by Heinrich Gustav Reichenbach (Reichenbach filius or Reichenbach f.), who was also an accomplished orchidologist.

Before being integrated into the larger collection, the Orchid Herbarium of Oakes Ames contained about 131,000 plant specimens, around 3,000 flowers in glycerin, 4,000 specimens in liquid, and hundreds of line drawings that supplement the specimens. The main collection is accompanied by the Orchid Library of Oakes Ames, which houses about 5,000 books, reprints, and journals. The Ames Herbarium includes important ancillary documentation, including beautiful and remarkably detailed drawings from herbaria collections around the world, plus illustrations and line drawings of orchids prepared by Blanche Ames, the wife of Oakes Ames.