Hieracium sect. Vulgata
- Family: Daisy Family – Compositae, subfamily Cichorioideae (formerly Chicory Family – Cichoriaceae)
- Growing form: Perennial herb. Runnerless.
- Height: 10–60 cm (4–25 in.). Containing milky latex.
- Flower: Single flower-like capitula 1–2 cm (0.4–0.8 in.) broad, surrounded by involucral bracts. Capitulum flowers yellow, tongue-like, tip 5-toothed. Stamens 5. Gynoecium composed of 2 fused carpels. Involucral bracts in many rows, overlapping, different lengths, narrowly triangular, sharp, varyingly with star and glandular hairs, base stellate-haired, inner bracts with narrowly membranous margins. Capitula same length, borne in a lax corymbose cluster.
- Leaves: Alternate on stem, sometimes also basal rosette. Rosette leaves 2–4, withering before flowering, sometimes dark-spotted. Stem leaves usually 2–5, short-stalked–stalkless, lowest same size as rosette leaves, upper small. Blade narrowly obovate–elliptic–lanceolate, usually with tapering base (sometimes blunt base), large–small-toothed (occasionally lobed), both sides with bristle hairs.
- Fruit: Uniformly thick–widening towards tip, ca.10-ribbed, reddish brown, 3–4.5 mm (0.12–0.18 in.) long achene, tip with ring-like border and slightly brownish unbranched hairs.
- Habitat: Open, dry and young forests (occasionally broad-leaved forests), logging clearings, forest margins, rocky outcrops, shores, meadows, banks, roadsides, wasteland.
- Flowering time: June–September.
Genus Hieracium is vast and very demanding as it consists of thousands of apomictic, asexually seed-producing micro-species. In Finland there is a long tradition of research into the genus, which has resulted in the identification of over 400 hawkweeds growing wild in the country. This huge range of varieties has been further divided into more practical larger groups, group species or sections. The largest group, common hawkweeds, probably contains about 140 species.
Genus Hieracium takes its name from the Greek word hierax, meaning ‘hawk’ as the birds were believed to drink hawkweed juice in order to keep their sight sharp. According to one interpretation, hawks would actually have used the capitula of mouse-ear hawkweed (Pilosella officinarum), which has nowadays, along with its relatives, been separated from other hawkweeds that they were formerly grouped with and put into their own genus Pilosella.
Common hawkweeds are often difficult to differentiate from wall hawkweeds (H. Sylvatica group), although their demands with regards to habitat are quite different. Common hawkweeds are common across Finland in logging areas in forests and on moors, meadows, banks and along shorelines, and they can often be found growing in areas that have been slightly culturally influenced. Wall hawkweeds are demanding and grow outwith the pale of human influence – many in fact seek asylum from human-influenced places. On the other hand there are wall hawkweeds that like cultural influence, and in the most extreme cases they can be found on park lawns having arrived mixed in with hayseed. Hawkweeds can be easily mixed up with other yellow-flowered members of the Daisy family, e.g. hawksbeards (genus Crepis). However, hawksbeards’ involucral bracts are overlapping in many rows while on other members of the Chicory subfamily the bracts are usually in two rows.