Species

Leptospermum scoparium var. incanum

Etymology

Leptospermum: slender seed
scoparium: like a broom

Common Name(s)

Manuka

Current Conservation Status

2018 - Threatened - Nationally Vulnerable

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Previous Conservation Status

2012 - At Risk - Declining
2009 - Not Threatened
2004 - Not Threatened

Qualifiers

2012 - DP

Authority

Leptospermum scoparium var. incanum Cockayne

Family

Myrtaceae

Brief Description

Small prickly shrub or small tree with flaky bark and hairy new growth and bearing masses of oval pointed leaves and, usually pinkish red-centred flowers. Endemic to northern Northland. Leaves rigid, 10-15 mm long by 1-2 mm wide, prickly to grasp. Flowers to 20mm wide. Fruit a dry 8-7 mm wide capsule.

Flora Category

Vascular - Native

Structural Class

Dicotyledonous Trees & Shrubs

Synonyms

None

Distribution

Endemic. Confined to the upper Northland Peninsula where it is abundant from Te Paki to Ahipara, and thence along the eastern coastline to Whangaroa. South of these stations it is locally present in mainly coastal shrublands, dunefield but also in some inland gumland scrub habitats. Exact southern limits are not, as yet clear.

Habitat

Abundant in coastal situations, especiallty dunefield, associated shrublands, gumland and on the margins of peat bogs.

Features

Shrub or small tree up to 5 m in height. Bark grey, peeling in long flakes, which become curled, and papery with age. Wood red. Branches numerous, arising from base, often suckering when covered in sand, and/or sprouting adventitious roots. Young branches, young leaves and flower buds clad in long silky, grey hairs. Leaves leathery (almost woody), very dark green, becoming subglabrous, narrowly lanceolate 10-15 x 1-2 mm, apex drawn out into a long stiff, sharp point, midrib not especially obvious, leaf margin finely crenate. Flowers solitary in leaf axils, up to 20 mm diam. Receptacle red or pink. Petals usually flushed pink or wholly pink, occasionally white or dark red. Stamens numerous. Capsule, long persistent and woody, 87 mm. Seeds numerous, straw-like, compressed 2.0 x 0.3 mm.

Similar Taxa

Easily distinguished from all other New Zealand and Australian forms of L. scoparium by the erect shrub habit, silky hairy leaves and stems, dark pink or pink flushed flowers, and by the very large capsule which scarcely opens except after fire or the death of the plant.

Flowering

Throughout the year but with a peak in late winter early spring.

Flower Colours

Red / Pink,White

Fruiting

The capsules are long persistent so invariably mature plants possess at least some capsules.

Propagation Technique

Very easy from fresh seed. Seed must be sown fresh, even if left for a few weeks before sowing viability can drop, especially if seed is allowed to dry out. Difficult from cuttings.

Threats

Not seriously threatened, though some stands are at risk from clearance for farmland or through felling for firewood. However, the recent (2017) arrival of myrtle rust (Austropuccinia psidii) may pose a more serious threat to Leptospermum (see below).

Chromosome No.

2n = 22

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

Where To Buy

Occasionally cultivated. One cultivar known as 'Cheryl Lee' was popular in gardens, and commonly sold by garden centres for a while during the 1980s. Extreme pink-flowered forms from the Karikari Peninsula may be the basis for some of the cultivars now popular. Leptospermum scoparium 'Keatleyi' seems to be an early wild selection of this variety.

Myrtle Rust Threat

Myrtle rust (Austropuccinia psidii) was first detected in New Zealand in 2017. As there is as yet no known effective treatment for that rust. Overseas indications are that this rust is having a serious impact on Myrtaceae worldwide, including causing such severe declines in some that extinction of some species and genera seems inevitable. As such the New Zealand Threat Listing Panel elected to list all indigenous Myrtaceae using the 'Precautionary Principle' as 'Threatened' (de Lange et al. 2018). Hopefully this assessment will be proved wrong. As of 2018 there have been very few occurrences of myrtle rust on Leptospermum. However, the rust is still in its early establishment phase. Australian experience suggests it may take 10 or more years to truly establish which New Zealand Myrtaceae will be most affected.

Fact Sheet Citation

de Lange, P.J. (Year at time of Access): Leptospermum var. incanum Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. http://www.nzpcn.org.nz/flora_details.aspx?ID=2186 (Date website was queried)

Attribution

Fact Sheet prepared for NZPCN by P.J. de Lange 1 February 2004. Description by P.J. de Lange.

This page last updated on 22 Dec 2018