Housed in a separate room from the main collection, OSAC owns a sizeable collection of soft-bodied specimens that are maintained in alcohol. This collection includes the majority of our aquatic insects and non-insect arthropods (spiders, scorpions, harvestmen, etc.). In addition to these, is a relatively large collection of larval insects (primarily amassed by Paul O. Ritcher).
Substantial portions of the H.J.Andrews Experimental Forest voucher material is stored in our wet collection. Aquatic insects, soil and canopy arthropods make up the bulk of this material.
Dr. Norm Anderson and his students spent many years researching the aquatic insects of the Pacific Northwest, and much of this material is now part of the OSAC wet collection. Trichoptera and Plecoptera collections from the Pacific Northwest are well represented.
In addition to arthropods, OSAC also maintains a growing collection of terrestrial and fresh water molluscs. Primarily comprised of PNW gastropods (snails and slugs) the collection also includes fresh water mussels.