''Gaudium laevigatum'', commonly known as the coast tea tree, is a species of shrub or small tree that is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to south-eastern Australia, but has been widely introduced in other places where it is often considered to be a weed. It has thin, rough bark on the older stems, narrow egg-shaped leaves, relatively large white flowers and flat topped fruit that is shed shortly after reaching maturity.

Description

''Gaudium laevigatum'' is a bushy shrub or tree that typically grows to a height of and has thin, rough bark on the older stems. The young stems are covered with silky hairs at first and have a groove near the base of the petiole. The leaves are greyish green, narrow egg-shaped with the narrower end towards the base, long and wide on a short petiole. The flowers are borne on short side shoots, usually in pairs of different ages, and are usually wide. There are many reddish brown

bract In botany, a bract is a modified or specialized leaf, associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves in size, color, shape or texture. They also lo ...

s around the flower buds but most fall off as the flower opens. The floral cup is mostly

glabrous Glabrousness () is the technical term for a lack of hair, down, setae, trichomes, or other such covering. A glabrous surface may be a natural characteristic of all or part of a plant or animal, or be due to loss because of a physical condition, ...

, long with the upper part expanded. The

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 Etymology The term ''sepalum'' ...

s are triangular, about long, the

petal Petals are modified leaves that form an inner whorl surrounding the reproductive parts of flowers. They are often brightly coloured or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corol ...

s white, long and the

stamen The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament ...

s long. Flowering mainly occurs from August to October and the fruit is a capsule wide with the remains of the sepals initially attached. The fruit mostly fall from the plant shortly after reaching maturity.

Taxonomy and naming

This species was first formally described in 1788 by

Joseph Gaertner Joseph Gaertner (12 March 1732 – 14 July 1791) was a German botanist, best known for his work on seeds, ''De Fructibus et Seminibus Plantarum'' (1788-1792). Biography He was born in Calw, and studied in Göttingen under Albrecht von Haller. H ...

who gave it the name ''Fabricia laevigata'' and published the description in his book '' De Fructibus et Seminibus Plantarum''. In 1858,

Ferdinand von Mueller Baron Sir Ferdinand Jacob Heinrich von Mueller, (; 30 June 1825 – 10 October 1896) was a German-Australian physician, geographer, and most notably, a botanist. He was appointed government botanist for the then colony of Victoria, Australia ...

assigned it to the ''Leptospermum'' genus as ''L. laevigatum'' in the ''Parliamentary Papers- Votes and Proceedings of the Legislative Assembly''. In 2023,

Peter Gordon Wilson Peter may refer to: People * List of people named Peter, a list of people and fictional characters with the given name * Peter (given name) ** Saint Peter (died 60s), apostle of Jesus, leader of the early Christian Church * Peter (surname), a sur ...

transferred Gaertner's ''Fabricia laevigata'' to ''Gaudium'' as ''G. laevigatum'' in the journal ''

Taxon In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...

''. The

specific epithet In Taxonomy (biology), taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin gramm ...

(''laevigatum'') is from a Latin word meaning "made smooth" or "having a polished surface".

Distribution and habitat

''Gaudium laevigatum'' is native to New South Wales, Victoria and Tasmania where it grows in heath, sometimes forest and on coastal dunes and cliffs south from Nambucca Heads in New South Wales to Anglesea in Victoria and northern Tasmania. It has also been introduced to Queensland, South Australia, Western Australia and countries overseas including southern Africa, New Zealand, Hawaii and the Central Coast of California.

Ecology

Coast teatree is salt-resistant, very

hardy Hardy may refer to: People * Hardy (surname) * Hardy (given name) * Hardy (singer), American singer-songwriter Places Antarctica * Mount Hardy, Enderby Land * Hardy Cove, Greenwich Island * Hardy Rocks, Biscoe Islands Australia * Hardy, ...

and is commonly used in amenities plantings and coastal plantings. It has also been planted in

Western Australia Western Australia (WA) is the westernmost state of Australia. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to the south, the Northern Territory to the north-east, and South Australia to the south-east. Western Aust ...

where it has become a weed. This species has been planted along the Central Coast of California in the United States and on the

Cape Flats The Cape Flats () is an expansive, low-lying, flat area situated to the southeast of the central business district of Cape Town. The Cape Flats is also the name of an administrative region of the City of Cape Town, which lies within the larger geo ...

Cape Town Cape Town is the legislature, legislative capital city, capital of South Africa. It is the country's oldest city and the seat of the Parliament of South Africa. Cape Town is the country's List of municipalities in South Africa, second-largest ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

, to stabilize

sand Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is usually defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural ...

. It is known in the United States as the Australian tea tree and in South Africa as the Australian myrtle. The seeds can be dispersed by wind and water. It has now become naturalised in

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

, southern

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

and

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

. The larvae of '' Holocola thalassinana'' feed on ''Leptospermum laevigatum''.

Use in horticulture

This species is planted widely (as ''Leptospermum laevigatum'') as a garden ornamental or display tree. It is useful as a

windbreak A windbreak (shelterbelt) is a planting usually made up of one or more rows of trees or shrubs planted in such a manner as to provide shelter from the wind and to protect soil from erosion. They are commonly planted in hedgerows around the ed ...

or hedging plant and for the rapid stabilisation of sandy soils, and in rehabilitation areas where construction or mining has taken place. It has begun to be cultivated for essential oil production, marketed as Coastal tree tree oil, and has shown some beneficial anti-microbial properties.

Conservation status

''Gaudium laevigatum'' is not listed on the advisory list of rare or threatened plants in Victoria (2014).

Gallery

File:Leptospermumlaevigatum42195793580 ec9792b069 o.jpg, Flower File:Leptospermumlaevigatumfruits38122870352 1f6deebb1e o.jpg, Fresh fruits File:Starr-020719-0016-Leptospermum laevigatum-BISH specimen seed capsule-Laie-Oahu (24468312811).jpg, Mature seed capsule

References

External links

Photo gallery
{{Taxonbar, from=Q722213 laevigatum Flora of New South Wales Flora of South Australia Flora of Tasmania Flora of Victoria (state) Myrtales of Australia Halophytes Plants described in 1788 Taxa named by Joseph Gaertner