Coreopsis in the Blue Mountains
Bushcare people call them weeds, but a mischievous friend of mine, who likes a laugh, calls them Mountain Daisies.
Every year late in spring they burst into flower in their millions along roadsides and the railway line — as they've been doing in the Blue Mountains for the better part of a century.
Their botanical name is Coreopsis lanceolata, and, yes, officially they are 'environmental weeds' in the Mountains, but with a history, or is it folklore, as bright as their brilliant yellow flowers.
They hail from central and south-eastern USA where they're also called Tickseed. As Florida's official state wildflower, Coreopsis is increasingly used for roadside plantings and highway beautification: "Nothing conveys the image of the Sunshine State better than a golden spray of Coreopsis spread across the landscape."
Coreopsis, or Calliopsis as they're also known, became popular with Australian gardeners as an easy-to-grow perennial; then, inevitably in those days, someone thought of using them to brighten up the bush.
The clearest evidence for this is from the Sydney Morning Herald's gardening writer - "Waratah" - in 1934:
A lover of colour is credited with throwing out handfuls of seed from the train windows to produce the effect which is now delighting so many train-travellers. We could do with more of these vagrant splashes on our otherwise prosaic landscape.
Five years later, "Waratah" could report:
Multitudes of calliopsis are at present providing a delightful display of colour along railway lines and roadsides about the city and well out into country areas.
The flowers have accommodated themselves to the vagrant state so well that their brightness increases in intensity and quantity each year. This year's display  on the Blue Mountains line is a byword with travellers. The story is that a daily traveller decided to relieve the tedium of the journey with bright blossoms by scattering seeds from the train window. His forethought has brought joy to thousands.
We need more of these bright touches in our landscapes, especially near the beaten tracks. This example could be followed on the southern highlands in the barer patches with cosmos or something equally adaptable.
In the same article, "Waratah" praised what has become one of Australia's worst agricultural and pastoral weeds:
Round the hills and flats of Gundagai a fine showing was recently provided by a so-called weed - Patterson's Curse [sic] - a purple carpet spread out for acres in a dazzling display.
The NSW Government's Fact Sheet on Patersons Curse sees it a little differently:
Paterson's Curse can completely dominate a paddock resulting in the endless fields of purple often seen in spring each year.
Although relatively nutritious in terms of digestible nutrients, and valued as a pasture plant in some places, Paterson's curse contains pyrrolizidine alkaloids that are poisonous to livestock as they can:
- destroy the liver
- reduce weight gain and wool clip
- lead to death in severe cases
In 1985, Paterson's curse was estimated to occur on over 30 million hectares in Australia, and in 2002 costing the wool and meat industries A$125 million each year.
Further proof that one person's much-loved plant can become a rampant problem for others.
Paterson's Curse is a declared noxious weed in the Blue Mountains, but Coreopsis carries the lesser official stigma of being a bush invader.
Today bushcarers rip them out with relish as they work on their patches. Back in 1934, though, "M.F.L." wrote lyrically about them to the Sydney Morning Herald after a car trip to the Mountains on a rainy day:
Then the rain lightened, ceased for a time, and suddenly, suddenly, the gold began. It was as if the sun god had sent out messengers laden with colour, to pour it over the sodden earth and dripping fences and running ditches — yellow coreopsis we name it here; sheets of them pouring down embankments, up to the very edge of the line and away on the other side, bubbling almost on the road, gleaming patches among tall tree trunks; edging up to garden fences and flaunting their gay little flags between more aloof flower faces.
And this for miles!
Sometimes there would come a little break, and then out again they would dance in their thousands, debonair, dauntless, heedless of soil or surroundings or gardener's care; asking nothing but light and air and some space, the more the better, and theirs the right to live and laugh. Darling flowers! Who would be dull in your company?
Coreopsis, however, has the habit of moving down stormwater drains and watercourses into virgin bushland. The official word is that its dense clumping habit and rapid spread can crowd out native plants and seriously reduce the germination of native seed. Look around the fringes of the national park and you may spot a few.
So, with our national parklands now protected by World Heritage listing, are these bush-invading "darlings" likely to disappear from our roadsides? Probably not, if only because the cost of removing them would be more than ratepayers are likely to sanction.
National Library of Australia – Trove website
Weeds of Blue Mountains Bushland website
CSIRO – Paterson's Curse fact sheet
Initial research by Bruce Howlett