Parietaria debilis
Common name
New Zealand pellitory
Synonyms
None (first described in 1786)
Family
Urticaceae
Flora category
Vascular – Native
Endemic taxon
No
Endemic genus
No
Endemic family
No
Structural class
Herbs - Dicotyledons other than Composites
NVS code
The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.
PARDEB
Chromosome number
2n = 16
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2017 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2012 and replaces all previous NZTCS lists for vascular plants. Authors: By Peter J. de Lange, Jeremy R. Rolfe, John W. Barkla, Shannel P. Courtney, Paul D. Champion, Leon R. Perrie, Sarah M. Beadel, Kerry A. Ford, Ilse Breitwieser, Ines Schönberger, Rowan Hindmarsh-Walls, Peter B. Heenan and Kate Ladley.
2012 | Not Threatened
Previous conservation statuses
2009 | Not Threatened
2004 | Not Threatened
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 greater in length than the perianth at fruiting. Parieteria debilis leaves are often very thin and membranous, and wilt easily once picking, but this is not a diagnostic character for plants of this 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.
Etymology
debilis: Weak
Where To Buy
Not commercially available.
Attribution
Description based on live plants and herbarium specimens.