HAS was created in 1971 to conserve the flora of Rio Grande do Sul, becoming the major part of its collection of material from this State, but with material of other states in Brazil, especially of Santa Catarina and São Paulo. The HAS Collection is accredited by CGEN/MMA as depositary of samples of the genetic component (Resolution Nº 5, 29.08.2002).
Nomenclatural types are 165, with digital photographic record. The most represented families are Asteraceae, Bromeliaceae, Fabaceae, Myrtaceae and Poaceae and also contains good collections od ferns and lichenized fungi. Maintains a reference collection of endangered species in RS.
The collection of algae currently has more than 14,909 bottles of liquid containing primarily microalgae and cyanobacteria in fresh water, with representatives of six major divisions and nine classes: Cyanobacteria, Chrysophyceae, Xantophyceae, Bacillariophyceae, Cryptophyceae, Dinophyceae, Euglenophyceae, Chlorophyceae and Zygnematophyceae. This collection also has more than 6,716 permanent slides of Bacillariophyceae. It is the herbarium with the largest number of bottles/ lots in liquid in Brazil.