Parietaria judaica
Encyclopedia
Parietaria judaica, common name Spreading Pellitory or Pellitory of the wall, is a species of herbaceous
Herbaceous
A herbaceous plant is a plant that has leaves and stems that die down at the end of the growing season to the soil level. They have no persistent woody stem above ground...

 perennial plant in the family Urticaceae
Urticaceae
Urticaceae, or the nettle family, is a family of flowering plants. The family name comes from the genus Urtica . Urticaceae includes a number of well-known and useful plants, including the aforementioned nettles, Ramie , māmaki , and ajlai .The family includes approximately 2600 species, grouped...

, commonly nicknamed sticky-weed. The plant's pollen
Pollen
Pollen is a fine to coarse powder containing the microgametophytes of seed plants, which produce the male gametes . Pollen grains have a hard coat that protects the sperm cells during the process of their movement from the stamens to the pistil of flowering plants or from the male cone to the...

 is highly allergen
Allergen
An allergen is any substance that can cause an allergy. In technical terms, an allergen is a non-parasitic antigen capable of stimulating a type-I hypersensitivity reaction in atopic individuals....

ic. In Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 it is also known as asthma weed, due to the high incidence of allergy. It is unrelated to the herb pellitory (Anacyclus pyrethrum
Anacyclus pyrethrum
Anacyclus pyrethrum is a perennial herb much like chamomile in habitat and appearance...

). It is easily confused with the very similar species Parietaria officinalis
Parietaria officinalis
Parietaria officinalis, the Pellitory-of-the-wall, also known as lichwort, is a plant of the nettle family. Its leaves, however, are non-stinging. The plant grows on rubbish and on walls, hence the name...

.

Description

The biological form of Parietaria judaica is hemicryptophyte scapose
Glossary of botanical terms
Many of the terms used in Wikipedia glossaries are already defined and explained within Wikipedia itself. However, lists like the following indicate where new articles need to be written and are also useful for looking up and comparing large numbers of terms together.This glossary is incomplete;...

, as its overwintering buds are situated just below the soil surface and the floral axis is more or less erect. This plant has pink or red hairy stems, woody at the base. It reaches on average 60 centimetres (23.6 in) in height.The leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....

 are hairy, alternate, simple, entire and green, with smooth margins. The tiny white or pink flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...

s are attached to the stems. They are bisexual
Plant sexuality
Plant sexuality covers the wide variety of sexual reproduction systems found across the plant kingdom. This article describes morphological aspects of sexual reproduction of plants....

, produced in clusters of three to many together in the leaf axils. The nickname sticky-weed is due to the adherent quality of the flowers and of the hairy stems; unlike some related nettle
Nettle
Nettles constitute between 24 and 39 species of flowering plants of the genus Urtica in the family Urticaceae, with a cosmopolitan though mainly temperate distribution. They are mostly herbaceous perennial plants, but some are annual and a few are shrubby...

s, the hairs do not sting. The flowering period extends from Spring through Autumn, when it produces large amounts of pollen. The fruits are blackish achenes.

Distribution

Spreading Pellitory is native to the Mediterranean but has become widespread in coastal areas of the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

, Australia, and North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

.

Habitat

Generally considered a weed
Weed
A weed in a general sense is a plant that is considered by the user of the term to be a nuisance, and normally applied to unwanted plants in human-controlled settings, especially farm fields and gardens, but also lawns, parks, woods, and other areas. More specifically, the term is often used to...

, it is often found on roadsides, along the dry stone walls and in cracks of buildings. However, it is useful in a habitat garden as it is a larval food plant for red admiral
Red admiral
Red admiral may refer to:Butterflies*Vanessa atalanta, a species of butterfly found in temperate Europe, Asia and North America*Vanessa gonerilla, a species of butterfly, also known as the New Zealand red admiral, found in New Zealand*Vanessa indica, a species of butterfly, also known as the Indian...

 butterflies. It is the host plant for the larvae of butterflies of the genus Vanessa
Vanessa
Vanessa can refer to:* A member service officer at SOMB.* Vanessa , a female given name coined by Jonathan Swift, originally as a nickname for Esther Vanhomrigh* Vanessa , a genus of butterflies...

. The ideal habitat is the dry places, at an altitude of 0–1000 m (0–3,280.8 ) above sea level.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK