Common name: Pellitory, Asthma Weed
Parietaria judaica L. APNI*
Synonyms: Parietaria diffusa Mert. & W.D.J.Koch APNI*
Description: Perennial herb with spreading to erect or procumbent stems to 80 cm long. Stems reddish to green. Single seeded dry fruit (achene) maturing dark brown to black, hard, 1–1.2 mm long and 0.6–0.9 mm wide.
Leaves with lamina rhombic, 1–5 cm long, 5–30 mm wide, lateral veins 2 or 3 pairs with the basal pair more prominent, both surfaces distinctly hairy, especially along veins; petiole mostly 5–20 mm long, generally shorter than the lamina.
Bisexual flowers numerous. Male and female flowers few.
Single seeded dry fruit maturing dark brown to black, hard, 1–1.2 mm long and 0.6–0.9 mm wide.
Flowering: Flowers for most of the year.
Distribution and occurrence: Native of Europe, western and central Asia and northern Africa, naturalised in the Sydney area and declared noxious.
Thrives in cracks, especially against walls. A common weed on roadsides, gardens and especially where there is seepage.
NSW subdivisions: *NC, *CC, *CT, *NWS, *CWS, *LHI
Other Australian states: *Vic. *W.A. *S.A.
A declared noxious weed in the Sydney region. Pollen can cause allergic responses in some individuals. Pellitory is also naturalised in North and South America and in New Zealand. In Australia, Pellitory is commonly confused with Parietaria debilis and Parietaria cardiostegia both of which are native annuals having mostly ovate leaves and almost stalkless (sessile) stigmas. The curled hairs on the plant make disperal easy by sticking to animals and people, especially from socks and trousers and machinery. Some local spread via root pieces and transport through water.
Text by G. J. Harden; updated Louisa Murray 2011.
Taxon concept: Flora of NSW 1 (1990); Noxious Weeds of Australia. W. Parsons and E. Cuthbertson, 1992, pages 622–624.
APNI* Provides a link to the Australian Plant Name Index (hosted by the Australian National Botanic Gardens) for comprehensive bibliographic data
***The AVH map option provides a detailed interactive Australia wide distribution map drawn from collections held by all major Australian herbaria participating in the Australian Virtual Herbarium project.