''Parietaria judaica'', with common names spreading pellitory or pellitory of the wall, is a species of

herbaceous Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition of t ...

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

plant in the family

Urticaceae The Urticaceae are a family, the nettle family, of flowering plants. The family name comes from the genus ''Urtica''. The Urticaceae include a number of well-known and useful plants, including nettles in the genus ''Urtica'', ramie (''Boehmeri ...

. The plant's

pollen Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophyt ...

is highly

allergen An allergen is a type of antigen that produces an abnormally vigorous immune response in which the immune system fights off a perceived threat that would otherwise be harmless to the body. Such reactions are called allergies. In technical terms ...

ic. In

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

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'', the pellitory, Spanish chamomile, Mount Atlas daisy, or Akarkara, is a species of flowering plant in the daisy family Asteraceae. It is native to Mediterranean Europe and parts of North Africa, but also naturalised in oth ...

''). It is easily confused with the very similar species '' Parietaria officinalis''.

Etymology

''Parietaria'' (Latin): Wall-dweller (a name used by the Roman naturalist and philosopher

Pliny Pliny may refer to: People * Pliny the Elder (23–79 CE), ancient Roman nobleman, scientist, historian, and author of ''Naturalis Historia'' (''Pliny's Natural History'') * Pliny the Younger (died 113), ancient Roman statesman, orator, w ...

). ''Judaica'' (Latin): Of Judaea, Jewish, from

Palestine __NOTOC__ Palestine may refer to: * State of Palestine, a state in Western Asia * Palestine (region), a geographic region in Western Asia * Palestinian territories, territories occupied by Israel since 1967, namely the West Bank (including East ...

Description

The biological form of ''Parietaria judaica'' is hemicryptophyte

scapose This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary o ...

, as its overwintering buds are situated just below the soil surface and the

floral axis The floral axis (sometimes referred to as the receptacle) is the area of the flower upon which the reproductive organs and other ancillary organs are attached. It is also the point at the center of a floral diagram. Many flowers in division Angios ...

is more or less erect. This plant has pink or red hairy stems, woody at the base. It reaches on average a height of . The

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

are hairy, alternate, simple, entire and green, with smooth margins. The tiny white or pink

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...

s are attached to the stems. They are

bisexual Bisexuality is a romantic or sexual attraction or behavior toward both males and females, or to more than one gender. It may also be defined to include romantic or sexual attraction to people regardless of their sex or gender identity, whi ...

unisexual Dioecy (; ; adj. dioecious , ) is a characteristic of a species, meaning that it has distinct individual organisms (unisexual) that produce male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproductio ...

, 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 species of the family

, 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 An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and indehiscent (they do not op ...

Distribution

''Parietaria judaica'' is a native of Europe, central and western Asia and northern Africa.

Allergy

Causes allergic reactions in some people.

Habitat

Generally considered a

weed A weed is a plant considered undesirable in a particular situation, "a plant in the wrong place", or a plant growing where it is not wanted.Harlan, J. R., & deWet, J. M. (1965). Some thoughts about weeds. ''Economic botany'', ''19''(1), 16-24. ...

, it is often found on roadsides, along dry stone walls and in cracks of buildings and rock faces. However it might be useful in a habitat garden within its native range, as it is a larval food plant for red admiral butterflies (''

Vanessa atalanta ''Vanessa atalanta'', the red admiral or, previously, the red admirable, is a well-characterized, medium-sized butterfly with black wings, red bands, and white spots. It has a wingspan of about . It was first described by Carl Linnaeus in his ...

''). Ideal habitats are dry and at an altitude of above sea level. This species is wind pollinated. Seeds are adhesive and transported by insects as well as other animals, people and machines.

Gallery

File:Parietaria judaica habitus on wall 2.jpg, ''Parietaria judaica'' habit on wall File:Urticaceae - Parietaria judaica (1).JPG, Plant of ''Parietaria judaica'' File:Urticaceae - Parietaria judaica-1.JPG, Stem and flowers of ''Parietaria judaica'' File:Urticaceae - Parietaria judaica (2).JPG, Leaf of ''Parietaria judaica''

References

External links

Jepson Manual Treatment: ''Parietaria judaica''
— ''invasive plant species'
Old link''Parietaria judaica'' — U.C. Photo gallerySchede di bitanica
* {{taxonbar , from=Q147991 judaica Flora of Asia Flora of Australia Flora of Europe Flora of North Africa Taxa named by Carl Linnaeus