Hieracium


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Related to Hieracium: Hieracium aurantiacum

Hieracium

 

(hawkweed), a genus of perennial pubescent herbs of the family Compositae. The leaves are entire or deeply toothed; the basal ones are usually in rosettes. The bisexual flowers are ligulate and usually yellow. They are in heads, which are solitary or gathered into a common inflorescence. The fruit is an achene. Many species reproduce by means of apomixis.

There are about 1,000 species (or 15,000 “small” species), distributed in the cold and temperate belts, primarily in the northern hemisphere. The plants also occur on tropical mountains. The USSR has about 700 species. The most common are H. pilosella and Ft. umbellatum. The former grows in meadows, in timber-felling areas, and along roads. H. umbellatum occurs in pine groves, in dry and floodplain meadows, on long-fallow land, and in fallow fields. Some species are cultivated as ornamentals.

REFERENCE

Iuksip, A. Ia. “Rod Hieracium L.—Iastrebinka.” In Flora SSSR, vol. 30. Moscow-Leningrad, 1960.

T. V. EGOROVA

References in periodicals archive ?
In contrast with the reference plot, these plots are grazed by sheep and have had significant modification of their vegetation, from dominantly tall tussocks of the genus Chionochloa to depleted short tussock and herbfield vegetation with the invasion of rabbits and the exotic weed Hieracium pilosella.
Mortier (1998) "Effect of extracts of Orthosiphon stamineus Benth, Hieracium pilosella L.
2000) postulated that in the dry greywacke steeplands, the prediction of soil distribution at the required scale (1 : 50 000) from traditional indicators was not useful in this geologically uniform area because the dominant ridge and valley landforms provide little indication of the soils on them; and the tussock, Hieracium, and scrub vegetation pattern (Newsome 1987) is largely the result of burning and grazing, and does not reflect soil patterns.
Another daisy with a similar growth habit called Hieracium pilosella has recently expanded its range in New Zealand.
Hawkweed ydi'r enw Saesneg arnyn nhw a Hieracium ydi'r enw gwyddonol.
The yellow Snowdonia Hawkweed - Hieracium Snowdoniense - disappeared 50 years ago and was thought to be extinct.
Saggar S, McIntosh PD, Hedley CB, Knicker H (1999a) Changes in soil microbial biomass, metabolic quotient, and organic matter turnover under Hieracium (H.
Effect of stand composition on insect visitation in two-species mixtures of Hieracium.
Die Reduktionsteilung und ihre Degeneration in Hieracium.
Thomson (1978) found that Hieracium florentinum received more visits from pollinators when it was mixed with H.