Inside the DEC Herbarium June 23, 2010Posted by broomegirl in Uncategorized.
Tags: collecting plants, herbarium, preserving plants, pressing plants
Did you know that the Department of Environment & Conservation’s Herbarium has 720 thousand specimens?
It is a remarkable collection of native leaves, algae, nuts, flowers and fungi, as well as exotic weeds. The Herbarium’s function is to document the biodiversity and distribution of native and “alien” plants, and their variations. It “underpins all the DEC’s conservation work .”
The Collections Manager at the Herbarium for the past five years is Karina Knight and she gave SKIPAs an interesting and deatiled presentation about what the facility’s work is about. She’s been working in this field for 26 years, starting fresh out of university when the Herbarium was part of the Department of Agriculture.
Karina explained that the ideal conditions for keeping pressed plants is 16 degrees and less than 50% humidity. Fluctuations allow insects to thrive or moulds to take over the collection. It is a constant challenge for staff to keep those foes at bay in the aging building, which was built to house only 250 thousand specimens.
“Humidity is the killer,” says Karina. She spoke of how some plants in the collection had been entirely eaten out leaving just dust.
A brand new puropse built herbarium is however nearly ready for the team to move into. But although the new one is just a kilometre up the road from the current facility in South Perth, it will take staff three months to shift the entire collection!
Karina says 20 to 25 thousand plants are sent to the Herbarium each year, but only 10 to 15 thousand can be processed. Costs associated with documenting such a large number are also prohibitive and the Herbarium will charge a lodging fee.
Work to document the plants is slow and painstaking. There are just a handful of staff (10 scientists, 6-12 technical staff, 2.5 in admin and 45 volunteers). Karina spoke about the minute details that are needed for their records, the cross referencing, cataloguing, mounting on acid free paper, and now website updates. A name change for a plant can add weeks of work to their job.
She explained that while much of the collection is pressed, bulky fruits or nuts are stored seperately (and cross referenced), and that some plants are stored in an alcohol-distilled water-glycerol solution. Algae is floated onto a sheet of paper and glued by its own natural agar. Delicate items are not taped but kept in acid free pockets. Pockets of plants are stored horizontally.
The plants of the Kimberley are a treasure trove the Herbarium is keen to know more about.
“Don’t presume that the Herbarium has a sample…. There is a need for more knowledge about the Kimberley.”
Karina described how to collect good samples; taking a good sized sample of the plant that includes fruit, flowers, leaves and bark. Good documentation is essential, using the Collection Book notes, and noting the terrain, environment or colour of the flowers. The sample then needs to be carefully pressed in newspaper.
“The Kimberley is the least explored region. One new taxon is found (from this region) for every 30 new specimens collected. Compare that with the rest of WA with 1 new species for every 338 collected. In the Wet every eight new specimens provide a new taxon.”
The Herbarium’s online presence with Flora Base is worth becoming familiar with, and an upgrade to the photos and information should make it even more useful for plant researchers. There’s also a Reference Herbarium, which can be used by students and scientists studying plants.And Karina said when staff are on hand they will happily answer questions from people in SKIPAs.
Well pressed plants can last centuries. Specimens collected by botanist Joseph Banks upon arriving in Australia are still in excellent condition in museums, while plants collected by William Dampier – in difficult circumstances – are also very well preserved.
Karina has an acacia named for her; Acacia karina, thanks to Bruce “Mr Acacia” Maslin.
“Bruce came in and said ‘great news I’m going to name a plant after you. You’ve got a choice of two plants – a tall spineless one or a dinosaur one.’ I chose the tall spineless one.”
It grows on banded ironstone east of Mingenew.
“It’s really special (to have a plant named after you).”