Family Matters

The Australian heaths have been generally classified as belonging to the plant family Epacridaceae, which takes its name from the well known genus Epacris. This classification is in a state of flux as a result of recent research which indicates that the Epacridaceae may be more closely related to the Erica family (Ericaceae) than previously thought, and it is likely that the family will be subsumed into the Ericaceae as subfamily Styphelioideae. The Ericaceae is widely distributed in the northern Hemisphere and Africa and includes such well known garden plants as Erica, Rhododendron, Azalea and Pieris. Prior to this recent research the Ericaceae was regarded as being poorly represented in Australia.

At least two Australian authorities (New South Wales and Western Australian herbaria) have either already adopted the re-classification or are in the process of doing so but until the re-classification is more widely adopted, ANPSA is retaining 'Epacridaeae' as a valid family in these web pages.

Characteristics

A general distinction between the Epacridaceae and the Ericaceae is the palmate venation of the leaves of most members of the former. "Palmate venation" refers to the way that several main veins radiate from the base of the leaf. Because of the small leaves in many species of the Epacridaceae, the veins often appear to be parallel.

	Palmate venation on Leucopogon lanceolatus

The present classification divides the Epacridaceae into 7 Tribes:

• Tribe Archeriaea - Comprises the single genus Archeria, which occurs in Tasmania and New Zealand.
• Tribe Cosmelieae - Three genera, the best known being Sprengelia.
• Tribe Epacrideae - Five genera including Epacris and Woollsia.
• Tribe Oligarrheneae - Comprises the two genera Needhamiella and Oligarrhena from Western Australia.
• Tribe Prionoteae - Two genera including Prionotes.
• Tribe Richeae - Three genera including Richea and Dracophyllum.
• Tribe Styphelieae - This is the largest Tribe. It includes Astroloma, Leucopogon, Lissanthe and Styphelia.

The Epacridaceae comprises around 34 genera and is distributed mainly in Australia but species are also found in countries to the north of Australia as well as in New Zealand, the Pacific islands and South America.

A number of species are attractive plants for cultivation due to their prolific and colourful flowers. The genus Epacris is the most commonly cultivated member of the family and one member of the genus, Epacris impressa (common or pink heath) is the floral emblem of Victoria. Apart from Epacris, other members of the family are not often seen in general cultivation but genera grown by enthusiasts include Astroloma, Dracophyllum, Leucopogon, Prionotes, Richea, Sprengelia, Styphelia and Woollsia.

Several members of the family were introduced into cultivation in Europe within a few years of British exploration of the east coast of Australia in the late 1700s - early 1800s. Species grown in Europe included species of Astroloma, Brachyloma, Epacris, Leucopogon, Lissanthe, Melichrus, Monotoca, Styphelia and Woollsia.

For the most part, the Australian heaths are small shrubs but a few species occur as small trees. They can be found in a range of habitats and are a common component of low, exposed vegetation known as heathland. Often they will be found in areas of constant moisture but also occur in temperate open forest and woodland, sub-alpine areas and the coastal zone. They tend to be absent in the arid zone and are rare in rainforests.

Small, fleshy fruit Leucopogon lanceolatus

The leaves are usually alternate or spirally arranged and sometimes sheathing around the stems. They are often stiff and can have a sharply pointed tip. The veins are generally narrowly palmate.

The flowers are usually tubular or cup-shaped with four or five spreading lobes and occur in spikes or racemes or occasionally solitary. The flowers usually have as many stamens as there are corolla lobes but there are some species in which male and female flowers occur on separate plants (dioecious) and in such cases, female flowers have only rudimentary stamens. Flowers are generally small but there are exceptions (eg. Prionotes and some Epacris).

The fruit is either a capsule which splits when ripe to release the seed or a drupe (a fleshy fruit with its seed enclosed in a hard stone).