Hieracium pilosella

Hieracium pilosella
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	Asterales
Family:	Asteraceae
Genus:	Hieracium
Species:	H. pilosella
Binomial name
Hieracium pilosella L.
Synonyms
Hieracium pilosella L. Hieracium pseudoincanum t.infr. Hieracium bauhinii Schult.t.infr. Pilosella bauhinii (Schult.) Arv.-Touv. Hieracium adenocladum (Rehmann) Czerep. Hieracium agathanthum (Rehmann) Czerep. Hieracium arvorum (Nägeli & Peter) Pugsley Hieracium callicymum (Rehmann) Üksip Hieracium cimpiense Prodán Hieracium cryptomastix (Nägeli & Peter) Freyn Hieracium cymanthodes (Koslovsky & Zahn) Üksip Hieracium cymanthum (Nägeli & Peter) Üksip Hieracium empodistum (Nägeli & Peter) Üksip Hieracium erythrophylloides (Zahn) Czerep. Hieracium fastigiatum (Nägeli & Peter) Üksip Hieracium georgieffianum Zahn Hieracium hispidissimum (Nägeli & Peter) Üksip Hieracium ingricum (Nägeli & Peter) Üksip Hieracium insolens Norrl. Hieracium limenyense (Zahn) Czerep. Hieracium macrum (Nägeli & Peter) Üksip Hieracium melachaetum Tausch Hieracium mnoocladum (Rehmann) Czerep. Hieracium obscuribracteum (Nägeli & Peter) Üksip Hieracium parvistolonum (Nägeli & Peter) Üksip Hieracium plicatulum Üksip Hieracium polyanthemum (Nägeli & Peter) Czerep. Hieracium pseudosparsum (Zahn) Czerep. Hieracium pseudothaumasium (Zahn) Üksip Hieracium radiocaule Tausch Hieracium rojowskii (Rehmann) Üksip Hieracium sedutrix (Rehmann) Üksip Hieracium spraguei Pugsley Hieracium stauropolitanum Üksip Hieracium thaumasioides (Peter) J. Weiss Hieracium thaumasium (Peter) J. Weiss Hieracium varatinense Woł. Hieracium viscidulum (Tausch) Üksip Pilosella adenoclada (Rehmann) Schljakov Pilosella agathantha (Rehmann) Schljakov Pilosella arvorum (Nägeli & Peter) Schljakov Pilosella botrychodes Schljakov Pilosella callicyma (Rehmann) Schljakov Pilosella chaunocyma (Rehmann) Schljakov Pilosella cryptomastix (Nägeli & Peter) Soják Pilosella cymantha (Nägeli & Peter) Schljakov Pilosella cymanthodes (Koslovsky & Zahn) Sennikov Pilosella dobromilensis (Rehmann) Schljakov Pilosella empodista (Nägeli & Peter) Schljakov Pilosella erythriophylla (Vuk.) Soják Pilosella erythrophylloides (Zahn) Schljakov Pilosella fastigiata (Nägeli & Peter) Schljakov Pilosella georgieffiana (Zahn) Soják Pilosella hispidissima (Nägeli & Peter) Schljakov Pilosella ingrica (Nägeli & Peter) Schljakov Pilosella insolens (Norrl.) Schljakov Pilosella limenyensis (Zahn) Schljakov Pilosella melachaeta (Tausch) Schljakov Pilosella mnooclada (Rehmann) Schljakov Pilosella obscuribractea (Nägeli & Peter) Schljakov Pilosella officinarum (L.) F.W.Schultz & Sch.Bip. Pilosella parvistolona (Nägeli & Peter) Schljakov Pilosella plicatula (Üksip) Schljakov Pilosella polyanthema (Nägeli & Peter) Schljakov Pilosella pseudosparsa (Zahn) Schljakov Pilosella pseudothaumasia (Zahn) Schljakov Pilosella rojowskii (Rehmann) Schljakov Pilosella sedutrix (Rehmann) Schljakov Pilosella thaumasia (Peter) Dostál Pilosella thaumasioides (Peter) Schljakov Pilosella varatinensis (Woł.) Schljakov Pilosella viscidula (Tausch) Schljakov

Hieracium pilosella (syn. Pilosella officinarum), known as mouse-ear hawkweed, is a yellow-flowered species of flowering plant in the daisy family Asteraceae, native to Europe and northern Asia. It produces single, lemon-coloured inflorescences. It is an allelopathic plant. Like most hawkweed species, it is highly variable and is a member of a species complex of several dozens of subspecies and hundreds of varieties and forms.

It is a hispid (hairy) perennial plant, with a basal rosette of leaves. The whole plant, with the exception of the flower parts, is covered in glandular hairs, usually whitish, sometimes reddish on the stem. The rosette leaves are entire, acute to blunt, and range from 1–12 centimetres (0.39–4.72 in) long and 0.5–2 centimetres (0.20–0.79 in) broad. Their underside is tomentose (covered with hair). The flowering stem (scape) is generally between 5–50 centimetres (2.0–19.7 in) tall, and sprouts from the centre of the basal rosette. The flowerheads are borne singly on the scape and are a pale lemon-yellow colour, with the outermost ligules having a reddish underside. It flowers from May until August and the flowers are visited by various groups of insects, especially flies.

The plant favours dry, sunny areas. It grows well on sandy and similarly less fertile ground types. It produces stolons which generate a new rosette at their extremity, each rosette has the possibility of developing into a new clone forming dense mats in open space. It also propagates by seeds.

It is a known allelopathic plant, whose roots secrete several substances inhibiting root growth, including its own. It can be controlled through rotation with clover and grasses where possible.

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Wikipedia