Olearia | |
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Olearia stuartii in Geelong Botanic Gardens | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Asterids |
Order: | Asterales |
Family: | Asteraceae |
Subfamily: | Asteroideae |
Tribe: | Astereae |
Subtribe: | Brachyscominae |
Genus: | Olearia Moench [1] |
Type species | |
Olearia tomentosa | |
Species | |
See text |
Olearia, most commonly known as daisy-bush, [2] is a genus of flowering plants belonging to the family Asteraceae, the largest of the flowering plant families in the world. Olearia are found in Australia, New Guinea and New Zealand. The genus includes herbaceous plants, shrubs and small trees. The latter are unusual among the Asteraceae and are called tree daisies in New Zealand. All bear the familiar daisy-like composite flowerheads in white, pink, mauve or purple.
Plants in the genus Olearia are shrubs of varying sizes, characterised by a composite flower head arrangement with single-row ray florets enclosed by small overlapping bracts arranged in rows. The flower petals are more or less equal in length. The centre of the bi-sexual floret is disc shaped and may be white, yellowish or purplish, generally with 5 lobes. Flower heads may be single or clusters in leaf axils or at the apex of branchlets. Leaves may be smooth, glandular or with a sticky secretion. The leaves may grow opposite, alternate, arranged sparsely or clustered. Leaf margins either entire or lobed, with or without a stalk. The fruit are dry slightly compressed, one-seeded, narrow-elliptic or egg-shaped with longitudinal ridges and smooth or with sparse hairs. [3] [4] [5]
The genus Olearia was first described in 1802 by Conrad Moench in Supplementum ad Methodum Plantas and is named after Johann Gottfried Olearius, a 17th-century German scholar and author of Specimen Florae Hallensis. [6] [7] Originally a large genus, a molecular study has found it to be polyphyletic. [8]
There are approximately 180 species of Olearia, of which about 112 species are endemic to Australia. Olearia are found in all states of Australia. [5]
The following is a list of Olearia species accepted by the Australian Plant Census or the New Zealand Plant Conservation Network or listed in the Census of Vascular Plants of Papua New Guinea as at May 2021: [9] [10] [11]
Several species are cultivated as ornamental garden plants, and there are hybrids of uncertain or mixed parentage. Among these, the following have been given the Royal Horticultural Society's Award of Garden Merit:- [12]
They are generally hardy down to −10 °C (14 °F), but require a sheltered spot in full sun.
Leucopogon is a genus of about 150-160 species of shrubs or small trees in the family Ericaceae, in the section of that family formerly treated as the separate family Epacridaceae. They are native to Australia, New Zealand, New Caledonia, the western Pacific Islands and Malaysia, with the greatest species diversity in the south-west of Western Australia. Plants in this genus have leaves with a few more or less parallel veins, and tube-shaped flowers usually with a white beard inside.
Prostanthera, commonly known as mintbush or mint bush, is a genus of about 100 species of flowering plants in the mint family Lamiaceae, and all are endemic to Australia. Plants are usually shrubs, rarely trees with leaves in opposite pairs. The flowers are arranged in panicles in the leaf axils or on the ends of branchlets. The sepals are joined at the base with two lobes. The petals are usually blue to purple or white, joined in a tube with two "lips", the lower lip with three lobes and the upper lip with two lobes or notched.
Epacris is a genus of about forty species of flowering plants in the family Ericaceae. It was formerly treated in a closely related but separate family Epacridaceae, but the various genera within Epacridaceae including Epacris have been revised in their relationships to each other and brought under the common umbrella of the Ericaceae. The genus Epacris is native to eastern and southeastern Australia, New Caledonia and New Zealand. The species are known as heaths or Australian heaths.
Pimelea, commonly known as rice flowers, is a genus of plants belonging to the family Thymelaeaceae. There are about 150 species, including 110 in Australia and 36 in New Zealand.
Pomaderris is a genus of about 80 species of flowering plants in the family Rhamnaceae, the species native to Australia and/or New Zealand. Plants in the genus Pomaderris are usually shrubs, sometimes small trees with simple leaves arranged alternately along the branches and bisexual, woolly-hairy flowers arranged in racemes or panicles. The flowers are usually yellow and often lack petals.
Cassinia is a genus of about fifty-two species of flowering plants in the family Asteraceae that are native to Australia and New Zealand. Plants in the genus Cassinia are shrubs, sometimes small trees with leaves arranged alternately, and heads of white, cream-coloured, yellow or pinkish flowers surrounded by several rows of bracts.
Swainsona is a genus of about 85 species of flowering plants in the family Fabaceae, and is endemic to Australia. Plants in this genus are herbs or subshrubs with imparipinnate leaves and usually purple flowers similar to others in the family.
Podolepis is a genus of flowering plants in the tribe Gnaphalieae within the family Asteraceae. It is endemic to Australia and can be found in every state.
Gompholobium, commonly known as glory peas or wedge-peas, is a genus of plants in the pea family Fabaceae and is endemic to Australia. Most species have compound leaves composed of three leaflets and all have ten stamens which are free from each other and a distinctive arrangement of their sepals.
Bossiaea is a genus of about 78 species of flowering plants in the pea family Fabaceae and is endemic to Australia. Plants in this genus often have stems and branches modified as cladodes, simple, often much reduced leaves, flowers with the upper two sepal lobes larger than the lower three, usually orange to yellow petals with reddish markings, and the fruit a more or less flattened pod.
Billardiera, commonly known as appleberries, snot berries, or bluebell creepers, is a genus of flowering plants in the family, Pittosporaceae and is endemic to Australia. Plants in the genus Billardiera are woody scramblers, climbers or twiners with elliptic, lance-shaped or linear leaves arranged alternately along the stems, the flowers with petals that are joined to form a tube at the base with spreading lobes, and succulent or fleshy fruit.
Lasiopetalum, commonly known as velvet bushes, is a genus of about forty-five species of flowering plants in the family Malvaceae, all endemic to Australia.
Spyridium is a genus of about thirty species of flowering plants in the family Rhamnaceae, and is endemic to Australia. Plants in the genus Spyridium are shrubs or subshrubs usually with small leaves, flowers usually in clusters of small composite heads, the individual flowers small and densely woolly-hairy, and the fruit a capsule. Species of Spyridium are found in all Australian states except Queensland.
Lepidosperma is a genus of flowering plant of the family Cyperaceae. Most of the species are endemic to Australia, with others native to southern China, southeast Asia, New Guinea, New Caledonia and New Zealand.
Styphelia is a genus of shrubs in the family Ericaceae, native from Indo-China through the Pacific to Australia. Most have minute or small leaves with a sharp tip, single, tube-shaped flowers arranged in leaf axils and with the ends of the petals rolled back with hairs in the inside of the tube.
Vittadinia is a genus of Australian and New Zealand plants in the tribe Astereae within the family Asteraceae.