When Europeans first arrived in the Canberra area, it was said that the open hillsides glowed yellow with yam daisy flowers - a delicious indigenous staple food. This little yellow flowered plant looks remarkably similar to a dandelion, but up close it is quite different.
Sadly today yam daisies are quite hard to find. Decades of sheep grazing has almost eradicated this plant from its former habitats. The yellow flowers you see around the suburbs, and increasingly in our national parks, are usually exotic dandelions and cat's ears.
So next time you're walking through the bush and you come across a yellow flower, how can you tell if it's really a yam daisy?
In this post I'll show you how.
At first glance, yam daisies (microseris lanceolata) look very like a dandelion (taraxacum officinale) or another, very similar-looking ubiquitous weed, cat's ear (hypochaeris radicata - also called flatweed, hairy cat's ear and false dandelion).
All plants are members of the daisy family (asteraceae) accounting for their similar features. All three plants are also edible - the roots and leaves of dandelions and cat's ear are both eaten (the leaves in salads and stir fries, and the roots of both can be roasted and used as a coffee substitute). I've only come across information about eating the root of the yam daisy though, not the leaves - and its roots are a lot yummier than the other two. All three plants are also perennials.
Below is a picture of the flowers from all three plants side by side for comparison. I was growing some yam daisies in a pot at the time and happened to find a dandelion and cat's ear in the lawn. You can buy yam daisies from specialist nurseries, and they're also fairly easy to propagate by seed.
On the left is the yam daisy, in the middle is the dandelion, and on the right is the cat's ear. I've noticed that there is quite a lot of genetic diversity among cat's ear plants, with some flowers a lot larger than others. As you can see, the one pictured is quite small, as many are around where we live in Canberra.
The most notable distinguishing feature of the yam daisy is that its petals are a little more sparse and widely spaced than the other two.
The second handy way to know for sure it's a cat's ear is to look very closely at the stem and you will see the tiniest little pointed upward pointing scales - about a milimetre in size, with little tufty dark hairs at the top of each every few centimetres along the stem. These tiny little leaflets (or whatever they are) are shaped like teeny little cat's ears - I was told this is how the plant got its name...
Looking at the backs of the flowers in the next picture, below, you can see they do look quite different. On the left is the cat's ear flower, showing the relatively narrow stem, and at the base of the flower, you can see some of the little 'cat's ears' - little green triangle shaped sections with dark tips. Although not shown in the picture below these also occured down the stem. In the middle is the true dandelion, which has a rather messier, almost hairy, base of the flower. The stem is considerably wider too, and when cut, you can see it's hollow, and it exudes a white latex around the cut. One the right is the yam daisy, quite a defined and smooth leaf base coming of a long, narrow stem. There are no straggly or hairy bits, and no scales along the stem.
In the background of this picture you can also see a seed head of a yam daisy. It is quite similar to a dandelion 'clock', but it is less fluffy and less dense, and a light tan in colour.
Yam daisies have another distinguishing feature - when the flower buds are still growing the head droops right down, only pointing upwards once the flower opens - see detail on right. Once it has finished flowering, the head again droops, before reopening as a seed head.
The leaves of the yam daisy are narrow, sometimes a little serrated, and much more slender than cat's ear leaves (which are rounded and slightly hairy) or dandelion leaves (which are large and jagged)
Below are a couple of pictures of a number of yam daisy plants in a pot, showing the relative size of the leaves, buds, seed head and flower.
In a small part of the Aranda bush land, after a prescribed burn, a number of yam daisies popped up in spring. This was about 2 years ago. In the subsequent wet spring of last year, with a lot more weed cover, I did not see any yam daisies. It may be that the yam daisy requires fire to eradicate the competition - I think I read that seeds were traditionally sown after fire by indigenous women.
Although they are not classified as endangered, the relative scarcity of yam daisies in the wild means it's not a good idea to try to harvest them. But they're pretty easy to grow, and as noted above, you can get them in nurseries and online.
I'll write about growing tips for yam daisies in another post - I've learned some interesting things about them!