Correa lawrenceana explained

Correa lawrenceana, commonly known as mountain correa,^[1] is a species of shrub or small tree of the family Rutaceae and is endemic to Australia. It has elliptical to egg-shaped leaves arranged in opposite pairs and cylindrical, greenish yellow to red flowers usually arranged singly or in groups of up to seven in leaf axils with the stamens protruding beyond the end of the corolla.

Description

Correa lawrenceana is a shrub that typically grows to a height of, sometimes a tree to, and has branchlets covered with rusty hairs. The leaves are arranged in opposite pairs, elliptical to egg-shaped, long and wide on a petiole up to long. The flowers are arranged singly or in groups of up to seven in leaf axils, rarely on the ends of branchlets, each flower on a pedicel long. The calyx is hemispherical to cup-shaped, long and wide. The corolla is cylindrical, greenish yellow to red with a scaly to velvety surface, long with four short lobes on the end. The stamens project well beyond the end of the corolla. Flowering occurs in spring and sporadically at other times.^{[2] [3]}

Taxonomy

This species was first described in 1834 by English botanist William Jackson Hooker who gave it the name Correa lawrenciana and published the description in his journal, The Journal of Botany.^{[4] [5]} The specific epithet honours Tasmanian botanist Robert William Lawrence (1807-1833) who, together with Ronald Gunn, collected the plant material sent to Hooker.^[6] In 1998, Paul Wilson corrected the name to Correa lawrenceana to conform to the Tokyo Code.^{[7] [8]}

A subgenus of Correa (Correa subgenus Persistens Othman, Duretto and G.J. Jord.) was formally described in 2011 comprising two species, C. lawrenceana and C. baeuerlenii.^[9] Unlike other Correa species, C. lawrenceana does not readily form hybrids with other species.^[10]

The names of eight varieties are accepted at the Australian Plant Census:

• Correa lawrenceana var. cordifolia Paul G.Wilson,^[11] commonly known as pink mountain-correa, is distinguished by its broadly elliptic to broadly heart-shaped leaves and hairy calyx long.^[12]
• Correa lawrenceana var. genoensis Paul G.Wilson,^[13] commonly known as Genoa River correa, is distinguished by its broadly elliptic to broadly heart-shaped leaves and glabrous green calyx long.
• Correa lawrenceana var. glandulifera Paul G.Wilson^[14] has elliptic or egg-shaped leaves, a shallow hemispherical calyx about long covered with star-shaped hairs and a yellowish green corolla.
• Correa lawrenceana var. grampiana Paul G.Wilson,^[15] commonly known as Grampians mountain-correa, has leathery, broadly elliptical leaves, a calyx covered with woolly rust-coloured hairs and a cylindrical corolla covered with velvety hairs.
• Correa lawrenceana. var. latrobeana (F.Muell. ex Hannaford) Paul G.Wilson^[16] is distinguished by its broadly elliptic to broadly heart-shaped leaves and hairy calyx long.
• Correa lawrenceana Hook. var. lawrenceana^[17] has narrow elliptical leaves long and a green corolla.
• Correa lawrenceana var. macrocalyx (Blakely) Paul G.Wilson^[18] is similar to var. cordifolia but has a calyx long.^[8]
• Correa lawrenceana var. rosea Paul G.Wilson^[19] has narrow elliptical leaves long, a calyx long and a narrow cylindrical corolla that is pink to dull red with green lobes.^{[8] [20] [21]}

Some varieties grade into each other, and the delineation between them is imprecise.

Distribution and habitat

The species is found in rainforest and sclerophyll forest in Tasmania, Victoria, New South Wales, the Australian Capital Territory and Queensland. Variety cordifolia grows in forest on the coast and tablelands of southern New South Wales, the Australian Capital Territory and far north-eastern Victoria. Variety genoensis is only known from the banks of the Genoa River near the New South Wales - Victoria border.^{[22] [23]} Variety glandulifera is found in the mountains from the Gibraltar Range in New South Wales to the McPherson Range in south-eastern Queensland. Variety grampiana grows among rocks in mountain areas, mainly in the Grampians. Variety latrobeana is found in south-eastern New South Wales and eastern Victoria. Variety lawrenceana occurs in mountainous areas in Tasmania and the Australian Capital Territory, var. macrocalyx is found in mountainous areas between the Taree and the Illawarra regions in New South Wales and var. rosea is only found in the Snowy Mountains of New South Wales.

Ecology

The flowers are presumed to be pollinated by either birds or bees.^[24]

Use in horticulture

Correa lawrenceana is suited to a cool, moist, partly shaded position and is known to tolerate frost and snow. It can be used as a screening plant and will attract honeyeaters to the garden.^[25] Plants are easily propagated from cuttings, whereas seed can be difficult.^[6]

Notes and References

1. Web site: Porteners . Marianne F. . Weston . Peter H. . Correa lawrenceana F.Muell.. Royal Botanic Garden Sydney . 12 July 2020.
2. Web site: Wilson . Paul G. . Wilson . Annette J.G. . Bolton . P.E. . Correa lawrenceana . Australian Biological Resources Study, Department of Agriculture, Water and the Environment: Canberra . 12 July 2020.
3. Web site: Duretto . Marco F. . Correa lawrenceana . Royal Botanic Gardens Victoria . 12 July 2020.
4. Web site: Correa lawrenceana. APNI. 12 July 2020.
5. Hooker . William Jackson . Contributions Towards a Flora of Van Dieman's Land; from collections sent by R. W. Lawrence, and Ronald Gunn, Esqrs., and by Dr. Scott. . The Journal of Botany . 1834 . 1 . 254 . 12 July 2020.
6. Web site: Correa lawrenceana. Australian Native Plants Society (Australia). 26 June 2011.
7. Web site: Correa lawrenceana. APNI. 10 July 2020.
8. Wilson . Paul Graham . Notes on the genus Correa (Rutaceae). . Nuytsia . 1998 . 12 . 1 . 96–99 . 12 July 2020.
9. Othman, Raja Nur Ateeka . Gregory J. Jordan . James R. P. Worth . Dorothy A. Steane . Marco F. Duretto. 2011. Phylogeny and infrageneric classification of Correa Andrews (Rutaceae) on the basis of nuclear and chloroplast DNA . Plant Systematics and Evolution. 288. 3. 127–138. 10.1007/s00606-010-0315-0. 22925844 .
10. Web site: Rutaceae. Duretto, Marco F.. Flora of Tasmania online. Tasmanian Museum and Art Gallery. 26 June 2011. 6 July 2011. https://web.archive.org/web/20110706122635/http://demo1.tmag.tas.gov.au/treatments/families/Rutaceae/Rutaceae_2009_1.pdf. dead.
11. Web site: Correa lawrenceana var. cordifolia . Australian Plant Census . 12 July 2020.
12. Wilson . Paul Graham . A taxonomic revision of the Genus Correa. . Transactions of the Royal Society of South Australia . 1961 . 85 . 44–51 . 12 July 2020.
13. Web site: Correa lawrenceana var. genoensis . Australian Plant Census . 12 July 2020.
14. Web site: Correa lawrenceana var. glandulifera . Australian Plant Census . 12 July 2020.
15. Web site: Correa lawrenceana var. grampiana . Australian Plant Census . 12 July 2020.
16. Web site: Correa lawrenceana var. latrobeana . Australian Plant Census . 12 July 2020.
17. Web site: Correa lawrenceana var. lawrenceana . Australian Plant Census . 12 July 2020.
18. Web site: Correa lawrenceana var. macrocalyx . Australian Plant Census . 12 July 2020.
19. Web site: Correa lawrenceana var. rosea . Australian Plant Census . 12 July 2020.
20. Book: Costermans, L.. Native Trees and Shrubs of South-eastern Australia . Rigby. Australia . 1981 . 978-0727014030.
21. Book: Wild Plants of Victoria (database). 2009 . Viridans Biological Databases & Department of Sustainability and Environment.
22. Web site: Porteners . Marianne F. . Weston . Peter H. . Correa lawrenceana var. cordifloia F.Muell.. Royal Botanic Garden Sydney . 12 July 2020.
23. Web site: Wilson . Paul G. . Wilson . Annette J.G. . Bolton . P.E. . Correa lawrenceana var. cordifolia. Australian Biological Resources Study, Department of Agriculture, Water and the Environment: Canberra . 12 July 2020.
24. Web site: Carter . Oberon . Walsh . Neville . National Recovery Plan for the Genoa River Correa Correa lawrenceana variety genoensis . Australian Government Department of the Environment . 12 July 2020.
25. Book: Greig, D.. The Australian Gardener's Wildflower Catalogue. Angus & Robertson. Australia . 1987 . 978-0-207-15460-7.