The New Zealand Plant Conservation Network

Species

Parietaria debilis

Etymology

debilis: weak

Common Name(s)

New Zealand pellitory

Current Conservation Status

2012 - Not Threatened

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

2009 - Not Threatened
2004 - Not Threatened

Authority

Parietaria debilis G.Forst.

Family

Urticaceae

Flora Category

Vascular - Native

NVS Species Code

PARDEB

Structural Class

Dicotyledonous Herbs other than Composites

Synonyms

None (first described in 1786)

Distribution

Indigenous. New Zealand: Kermadec (Raoul, Macauley), Three Kings, North, South and Chatham Islands. Present throughout southern hemisphere.

Habitat

Coastal and lowland. Usually in coastal scrub and forest (often found within canopy gaps or around petrel or shearwater burrows), or under rock overhangs or amongst flax. Sometimes growing in the open on exposed rock stacks or in sand dunes.

Features

Succulent-stemmed, spreading, flaccid to erect, diffuse, sparsely pubescent, annual herb forming solitary stems or tufted patches up to 500 mm diameter. Branches succulent, slender, weakly erect to erect, up to 800 mm long, pale green, translucent white or pale pink, usually hardened at base. Leaves membranous, mostly thin and delicate in shaded sites and subsucculent in exposed sites growing on guano. Petiole filiform to subterete, 10-60 mm long. Lamina 10-60 × 10-30 mm, pale green to dark green above, paler below (very rarely pink-tinged), suborbicular, broad-ovate, rhomboic-ovate, base cuneately narrowed, apex obtuse to weakly acuminate. Inflorescence a greenish-white, congested 2-8-flowered cyme; bracteoles linear, bracteoles equal to or more usually larger than perianth at fruiting; perianth-segments more or less pilose, pistillate enlarged in fruit. Achenes 1.0-1.5 mm long, dark glossy brown, ovoid.

Similar Taxa

Distinguished from the two other naturalised pellitories (P. judaica and P. officinalis) by its annual growth habit, petioles usually longer than the leaf blade; and by the bracteoles which are equal to or or greater in length than the perianth at fruiting. Parieteria debilis leaves are often very thin and membranous, and wilt easily one picking, but this is not a diagnostic character for plants of thsi species which grow in richly manured soils in exposed coastal situations, as these plants may have very fleshy, succulent leaves. As a rule Parietaria debilis is a pale green to dark green colour, while the other two naturalised species often have red or pink-pigmented stems and leaves. However, sometimes these colours are seen in Parietaria debilis as well.

Flowering

Throughout the year

Flower Colours

Green

Fruiting

Throughout the year

Propagation Technique

Easily grown from fresh seed, soft wood cuttings and rooted pieces. However, not an especially attractive plant and unlikely to be widely cultivated. It is rather variable with respect to leaf shape and there is some genetic basis to this variation worth exploring. For example Chatham Island plants often have very small (10 x 10 mm) suborbicular leaves, which is retained in cultivation.

Threats

Not Threatened

Chromosome No.

2n = 16

Endemic Taxon

No

Endemic Genus

No

Endemic Family

No

This page last updated on 3 Jan 2014