Tuesday, 10 June 2014

Desert Pea a black-bossed bloom in buccaneer's bounty


With four weeks until Melbourne's Royal Botanic Gardens exhibits its, and Australia's, first show garden at the prestigious (UK's largest and best attended) Royal Horticultural Society Flower Show at Hampton Court Palace in west London, I thought I'd feature a few of the plant species you'll see in Essence of Australia (#EssenceOfAus in the Twittersphere).

None of the plants are particularly odd or unusual to us Australians. In fact designer Jim Fogarty has selected plants that are easy to source and can be grown - some under glass, some as annuals - relatively easily in the UK. The design is deceptively simple but evocative, and the plants similarly so.

So one a week, for the next four weeks. The first is a showy but infrequently grown species with a knotty knomenclature, Sturt's Desert Pea.


While it looks good in almost any setting it's worth seeking it out in the near-deserts of central Australia, in all of Australia's mainland states except Victoria. As the wonderful Australian National Botanic Gardens website puts it, look out for calcareous, sandy soil in small depressions which channel water before it percolates into the soil.

Or, you can find it in most Australian botanic gardens and, since 1855, in the UK, where it was originally grafted onto the Bladder Senna, Colutea arborescens. These days it is sometimes grafted onto the similar looking, but not as closely related as some thought, New Zealand Parrot Pea, Clianthus puniceus.

Sturt’s Desert Pea was discovered by English buccaneer and early Australian tourist, William Dampier, on 1 September 1699. He was visiting Rosemary Island in the Dampier Archipelago, a group of 40 or so islands in northern Western Australia. Dampier collected a herbarium specimen (one of 10 species sampled) from “a creeping vine that runs along the ground ... and the blossom like a bean blossom, but much larger and of a deep red colour looking very beautiful". The flattened flowers and branch are now in the Sherardian Herbarium, Oxford (UK).


English, and Sydney, botanist Allan Cunningham collected it 119 years later from the same archipelago and Benjamin Bynoe, surgeon on the voyage of HMS Beagle with Charles Darwin, found it when he visited an island in the neighbourhood in 1840.

Inland explorer Captain Charles Sturt saw the plant in 1844, somewhere between Adelaide and central Australia, and his name is now attached to its otherwise very helpful common name. In scientific nomenclature, ‘Swainsona’ honours Isaac Swainson, who had a private botanic garden at Twickenham (a suburb of London) around 1789 and ‘formosa’, appropriately, is Latin for beautiful.

All sound simple, but it took some time to get there. In 1832 this unforgettable plants was finally described scientifically as Donia formosa, by Scottish Botanist George Don. His was an optimistic assignment given that Robert Brown described the genus Donia in 1813, based on Donia glutinosa (which is now Grindelia hirsutula) an American weedy daisy with yellow flowers commonly called Hairy Gumweed.

In 1835 is was more sensibly moved to Clianthus, a genus then and now confined to New Zealand and commonly called Parrot’s Beak. The flowers are similarly big and bold, and at least it's a pea. But this genus is now known to be unrelated to Sturt’s Desert Pea.

(When moved to Clianthus it was given the superfluous but nicely relevant species name dampieri; the species name formosa should have been retained. In 1950, this problem was fixed and it was for a few decades called Clianthus formosus - the ending gets adjusted to fit the gender of the genus name).

Then in 1990 it was moved to Swainsona, as Swainsona formosa, where it fits well in terms of our modern understanding of its form and its genetics. And there it remains, petty much.

There was a footnote in 1999 when Western Australian botanist Alex George thought its distinctive form warranted it being separated from other Swainsona, and set up a new genus Willdampia honouring William Dampier. But this would leave the rest of Swainsona unviable as a genus (we call it ‘paraphyletic’, when the taxonomic group doesn't include all the extant species from a common ancestor).

I hope I have all that correct. In any case, it's a black-bossed, beautiful blossom by any binomial.


Images: the top two are from a garden planting in Alice Springs (July 2008), a region where it grows naturally, and the bottom two from Australian National Botanic Gardens' new Red Centre Garden (March 2014).

1 comment:

Bort said...

Willdampia indeed.
Sent me down a lexicographical rabbit hole that ended in "phatic" and "wonder clout"...