Herbarium maintenance procedures
CDF is happy to share the procedures followed in its Herbarium for the benefit of curators and researchers working in similar fields.
Pest control
Atmospheric control
Supplementary collections
Mounting
Herbarium database
Quarantine procedures
Pest control
Conditions in tropical regions with high temperatures and humidity allow rapid growth of pests that require continuous control. The herbarium's collections are subject to attack by numerous pests that affect the specimens. In order to reduce this problem, all collections pass through a freezing process before entering the herbarium.
Since January 2000, a pest control program using monitoring traps and the biodegradable insecticide Pyrethrum was implemented. Its quick action paralyzes insects, and has a very low level of toxicity for humans and plants. The same insecticide is taken to other islands when botanical collection fieldtrips are undertaken to avoid introducing insects from one island to another.
Traps have been set in the herbarium in order to monitor insect pests. These traps are manufactured with a special type of glue that attracts and traps the pests. Each trap contains a dated label, trap number and code. These are distributed in strategic places throughout the herbarium.
Of pests caught in traps, ants and isopods are the most frequent. These pests adapt to various extreme conditions and their main food source includes live and inert plants, including sugars and proteins.
Atmospheric control
Temperature and humidity are measured, working to maintain an optimal state in the herbarium. The optimal temperature is 20-23º C and the humidity is 40-60%.
Supplementary collections
Collections in alcohol
In the herbarium, a mixture called the "Copenhagen Mixture" is used, composed of 70% alcohol, 29% water, and 1% glycerol. This last component is very important as it prevents the structures from changing color. Our collections of algae, fruits, and flowers are preserved in this way.
Dry collections
Collections of fruit, trunk portions, bark, roots, etc. form part of the supplementary collection, as many are too large to be mounted. Upon arrival to the herbarium, these are frozen for a maximum of three days to kill possible pests.
Seed collections
Paper bags and silica gel are used to preserve seeds in the field, which then go through a freezing process to kill potential pests. The seeds are preserved in glass jars or sealed bags with their respective labels.
Within all categories of the supplementary collections, the Station is developing photographs and slide collections of the species. This will be in addition to the photograph collection currently maintained in the herbarium for native, endemic, and introduced flora of Galapagos.
Pollen reference collection
The herbarium is currently working to develop a pollen reference collection. Once implemented, this will serve as an essential tool to help in studies such as seed and pollen dispersal and phenology of the different plant species through the pollinators and their mediums of transportation.
Mounting specimens
Special glue is used to mount the plants that in the future allow the specimen or part of it to be removed if needed for a study (i.e. DNA studies, vegetable anatomy, etc.)
Quarantine procedures
Scientists collecting specimens from various islands have to follow strict quarantine procedures. Like other isolated island ecosystems, the Galapagos archipelago has many endemic species, unique species not found anywhere else in the world. To protect these species, accidental transport of introduced species and pests between islands must be avoided. Separate populations of native species from different islands must also remain isolated. Specimens can only be collected for research projects with a clear focus on conservation, and after approval by the Galapagos National Park (GNP). This ensures that scientific exploration will not inadvertently harm native populations.
CDRS Herbarium - introduction
History of the CDRS Herbarium
About the Herbarium collections
Access to the CDRS Herbarium
2006 Herbarium projects
The CDRS Herbarium is supported by Discovery Initiatives Ltd, UK.
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