Olearia asterotricha

Olearia asterotricha, commonly known as rough daisy-bush, is a species of flowering plant in the family Asteraceae. A tall shrub with white, mauve or blue daisy like flowers growing from the Blue Mountains in New South Wales to western Victoria, Australia.

Description
Olearia asterotricha is small sprawling shrub to  high and  wide with an open habit. The branchlets are covered with densely matted woolly hairs, star-shaped hairs or a combination of both.
.  It has   white, pale mauve or blue daisy like flowers with a yellow or purplish centre. The flowers are  in diameter and  solitary or 25-40 per cluster and appear at the end of stems. Each inflorescence is on a peduncle about  long. The bracts have fine short matted hairs and arranged in rows of 1-3. The dark green leaves are arranged alternately, sometimes with a very small stalk or without a stalk. The leaves are broadly-linear or oblong shaped,   long and  wide with rough star shaped hairs on the upper side of the leaves and stems. The underside of leaves is densely woolly, leaf margins are entire or toothed and rolled under. The fruit is cylindrical shape about  long with 6-8 ribs about  long. Fruit are smooth to sparsely covered with matted hairs. It contains a dry single seed that does not open on maturity.

Taxonomy and naming
Rough daisy bush was first described in 1859 by Ferdinand von Mueller as Eurybia asterotricha and published in Fragmenta Phytographiae Australiae.  In 1865 Mueller changed the name to Aster asterotrichus. In 1867  English botanist George Bentham changed the name to Olearia asterotricha. 

Four subspecies are recognised by the Australian Plant Census:  
  Olearia asterotricha  subsp. asterotricha, is an upright shrub with mostly linear leaves about  long and  wide. The leaf edges may be wavy, rolled under, bent or slightly lobed.  
In 2014, Andre Messina described three of the subspecies and published the descriptions in Australian Systematic Botany: 
  Olearia asterotricha subsp. glaucophylla has bluish leaves, lobed edges from about halfway to apex and very small white protuberance at the leaf base;   
  Olearia asterotricha subsp. lobata is a spreading shrub with linear, oblong or egg-shaped about  and  wide. Leaf margins are curved or flat and lobed. Flowers appear singly or in clusters of 2 or 3 on occasion 5.  Blooms from October to December;
  Olearia asterotricha subsp. rotundifolia is a rounded erect shrub. The leaves are broadly egg-shaped, sometimes slightly narrower,  long and  wide. The leaf margins  may be flat to slightly recurved, slightly lobed or with wavy depressions. Flowers are in clusters of 3 on a stalk  long with a small mauve protuberance at the leaf base. This species flowers in December.

Distribution and habitat
Rough daisy bush grows from the Blue Mountains, New South Wales to western Victoria where it grows mostly in cool damp acidic soils, heath, or dry sclerophyll forest. The species may vary depending on geographic region.  In the Sydney region it is a compact shrub with white flowers and grey-green foliage. The Victorian form has mauve-blue flowers, green leaves and a more open form. Considered rare in Victoria.
  Olearia asterotricha  subsp. asterotricha is only found at elevated sites in the Grampians National Park growing on sandy soils in heath woodlands.

  Olearia asterotricha subsp. glaucophylla grows  north of Mittagong in New South Wales.
  Olearia asterotricha subsp. lobata grows in wet heathland or in moist forest usually found at lower altitudes. Also found in a few disjunct areas of southern Victoria  but usually uncommon.

  Olearia asterotricha subsp. rotundifolia is believed to be restricted to a single population directly below the summit of Mt Langi Ghiran, Victoria. Growing in damp situations on southern slopes around granite boulders.

References

Category:Asterales of Australia
Category:Flora of New South Wales
Category:Flora of Victoria (Australia)
asterotricha