Olearia, named in honour of German botanist J.G.Oelschlaeger, is a genus of daisy bushes in the family Asteraceae. This genus occurs only in the southern hemisphere. Australia has approximately 130 of the 180 species.
Landing by helicopter on Maatsuyker Island on Dec 6, 2011, the “sprinkle of sugar” giving the island vegetation its white coating was made up predominantly of the masses of white flowers of Olearia phlogopappa and the tea-tree, Leptospermum scoparium.
Species name phlogopappa is from two Greek words, phlogos, flame, and pappos, pappus, a group of appendages (often hairs or scales) attached above the ovary in members of the daisy family. The original description of this species alludes to the pappus being flame-coloured.
O. phlogopappa, the Alpine Daisy Bush, is a shrub that grows to about 160cm high with dense branches and leaves. The flower-heads are numerous, terminal at the end of short axillary branches along the stem. The flower-heads are about 2cm in diameter with 20-26 florets. Those I saw were all white, although the reference material indicates they can occasionally be blue or purplish.
The leaves are alternate, about 0.8-4 cm long and 3-10mm wide, with toothed margin. The upper surface of the leaf is bright green with scattered stellate hairs, while the under surface has dense stellate hairs, making it appear white-grey. The achenes (fruit) are about 2.5mm long, and hairy.
Considering its exposure to harsh sea winds, this species was doing very well, especially on the south-west facing slopes of the island.
O. persoonioides, common name Geebung Daisy Bush, or Mountain Daisy Bush. According to “The Encyclopaedia of Australian Plants“, the species name arose because “it is similar to genus Persoonia. It was named by English botanist George Bentham who lived from 1800 to 1884.
The flower-heads are stalked with 3-5 together on a peduncle in the upper axils. The ray florets (outer) are white, between 12-16. The disc florets (centre) are yellow.
The leaves are elliptical, dark green, shiny on the upper surface and white with dense short hairs on the lower surface.
Extract from my Maatsuyker Island Native Plant Project book:
“The plant list has three Olearia species listed. O. phlogopappa is -everywhere- and has been flowering throughout December and January. O. persoonioides is common along the top (eastern) side of the track to the Red shed, also flowering throughout December and January, but not as prolifically. However, despite hunting high and low, I have not found the third listed species O. viscosa. Its leaves are quite distinctive, according to the reference books – opposite and long. The leaf of persoonioides has a lot of variation in both size and shape, including some that look like the photos of viscosa, but they are definitely -not- opposite.”
Here is a photo of my WIP graphite drawing of the Olearieas… O. persoonioides almost done. I am showing the open flowers, new buds, leaves and in the bottom left, the metallic-shiny remnant bracts and seed pods.