NTBG’s herbarium grew by 1,791 specimens in 2014 and currently holds over 72,000 vouchers. The databasing and barcoding of 43,500 specimens plus the photographing of 33,700 specimens was accomplished, making these data publically available. The herbarium specimens are one of the NTBG's oldest collections and are housed at the institution's research headquarters in Hawai'i. They consists of preserved, dried and pressed plant specimens (vouchers), which serve as a considerable resource for scientific research, including floristic and systematic studies. The collections concentrate on plants of the Hawaiian Islands and the tropical Pacific region. The institution has amassed the most comprehensive modern collection of vouchers of Hawaiian and Marquesan plants anywhere, including a number of species that are extinct. Plant specimens are acquired through hundreds of collecting expeditions by NTBG field botanists, as well as gifts for identification and exchanges with other institutions. Each specimen is meticulously documented. It is identified by botanical experts and detailed information is recorded about the location where plant was collected. The value of NTBG's herbarium collections is enhanced by its proximity to the living collections and to the library collection.