Pastinaca (Apiaceae for Flora Nordica)

Hemicryptophyte. Stout biennial, to 150 cm; taproot 6–18 mm thick; both root and leaves with an aromatic scent. Stem solid, or secondarily hollow; basal part 3–10 mm thick, distinctly to indistinctly sulcate or rarely angular, purplish or greenish, slightly glaucous or not, often ± papillose to hairy (hairs deflexed, to c. 1 mm); upper internodes distinctly to indistinctly sulcate, ± papillose. Leaves 2–6 at the base and (3–)5–13 on the stem (the innermost basal one is usually the largest); sheath rather narrow, rarely purplish; petiole 6–14(–23) cm; blade 1(–2)-pinnate, 7–19(–24) × 6–12(–16) cm (length/width ratio 1.2–1.9), lower side glabrous to densely papillose (rarely hairy), upper side glabrous to sparsely papillose. Primary leaflets 3–5(–9) pairs; angle leaflet/rachis 45–80°, decreasing towards the apex. Apical leaflet 1–2-pinnatifid, with 1–3(–4) pairs of lobes; petiolule 6–23(–27) mm; blade (22–)31–65(–80) × (20–)27–75 mm (length/width ratio 0.8–1.2); base cordate to truncate, rarely broadly cuneate; apex acute to obtuse; margin doubly serrate in upper part, usually with purplish tips. Lateral leaflets entire or 1-pinnate with 1–2(–6) pairs of lobes; petiolule 0(–4) mm; blade ovate to elliptic, (18–)29–62(–75) × 16–53 mm (length/width ratio 1.1–2.1); base broadly cuneate to cordate, unequal; apex usually acute; margin doubly serrate in upper part.

Umbels flat to slightly convex, 3–4(–5) cm high and 8–10(–17) cm wide; peduncle 4–10 cm; rays straight or bent inwards, 3.3–5(–7.7) cm, glabrous or papillose on the adaxial side. Bracts 0(–4), persistent. Umbellules 8–23(–42); pedicels 0.6–1.3 cm, glabrous or papillose on the adaxial side. Bractlets 0(–2), persistent. Flowers 15–35(–42) per umbellule; sepals absent; petals pale yellow, 0.8–1.3 × 0.7–1.1 mm, entire; filaments 1–2 mm; anthers 0.4–0.6 mm. Fruit broadly elliptic to almost orbicular in outline, distinctly dorsiventrally flattened; carpophore filiform, divided to the base. Mericarps 4.7–7.3 × 3.8–5.8 × 0.4–0.8 mm (length/width ratio 1–1.6); ridges yellow-green to brown-green, 3 low central ones, and 2 lateral ones developed as wings (0.3–0.5 mm wide from the lateral veins); vittae yellow-brown to red-brown, 4 dorsal ones reaching downwards 70–90 % of the mericarp length, and 2(–4) shorter ventral ones; stylopodium flattened, 0.9–1.3 mm wide; style 0.6–0.9 mm, deflexed. – Early summer to autumn.

Distribution. Nem–SBor(–MBor). – Cultivated since the Medieval, and archaeophytic in D and southernmost S, elsewhere a later introduction; in the 19th century recorded occasionally as an escape or an introduction (e.g. with ballast), during the 20th century becoming more frequent and reaching its present distribution, spreading with shipping, railways and road traffic (in northern N also a wartime incomer), but in general not directly from cultivation; increasing. – D common in the northeast and east except Brn, elsewhere scattered. N scattered around Oslofjorden and along the southern coast from Øf Hvaler to VA Mandal; casual and rare to fairly rare in He and Op (around Mjøsa), and on the western coast and in the fjords from Ro Time to NT Trondheimsfjorden (resident in ST Trondheim); NNo Bodø, Tr 4 records, and ØFi Sør-Varanger. S fairly common to scattered in the southern lowlands north to Dls, Vg, southeastern Dlr and Upl; further north rare and partly casual. F common as established in the densely populated areas in V, U and EH, elsewhere fairly rare to scattered north to central St and central PS; casual further north to KP Raahe, OP Oulu and PeP Tornio.

Habitat. Dry to mesic, nutrient-rich, clayey or sandy soil, usually in full sun; probably favoured by fertilization and overgrowth. Mainly on open man-made ground (roadsides, railways, fields, ruderal places), sometimes also in seminatural habitats (e.g. seashores) or in overgrown artificial grassland.

Variation. Pastinaca sativa is a polymorphic species. In Europe, it has been subdivided into three fairly widespread taxa, viz. subsp. sativa, subsp. sylvestris (Mill.) Rouy & Camus and subsp. urens (Godr.) Čelak. (Thellung 1926, Tutin 1968). Thellung recognized subsp. sylvestris with hesitation and regarded it as an intermediate between subsp. sativa and subsp. urens. Reduron (2008) included subsp. sylvestris as a variety (var. arvensis Pers.) within subsp. sativa. Subsp. urens is characterized by terete, usually hairy stems, hairy leaves with ± rounded, entire leaflets, and primary umbels with 5–7 rays, while subsp. sativa and subsp. sylvestris both have a sulcate stem and primary umbels with more than 8 rays. Subsp. sylvestris has mainly been distinguished from subsp. sativa by having long, wavy hairs and shorter leaflets with a more rounded apex; in subsp. sativa stems and leaves are glabrous or covered with short, stiff hairs/papillae, and the leaflets are ± elongated and distinctly lobed.

Subsp. sylvestris has been recorded several times from Norden. Many of the reports were based on material which clearly belongs to subsp. sativa, but morphotypes with long and wavy hairs have indeed been collected in N Øf (partly ballast) and Te, S northern Gtl (recent), Mpd and Ång (ballast), and F U (ballast; cf. Suominen 1979). These specimens probably represent several separate introductions (see e.g. Lid & Lid 2005, Suominen 1979). The hairy Nordic material has sulcate stems and large primary umbels as in subsp. sativa, but the shape of the leaflets is variable, and the material does not make the impression of a coherent taxon. Subsp. sylvestris is therefore not accepted here, and the strongly hairy morphotypes are referred to P. sativa s.lat. – Subsp. urens has recently been found at one locality in D FyL.

Subsp. sativa has been further subdivided into a tuberous morphotype (var. hortensis Gaudin) and a non-tuberous morphotype (var. pratensis Pers.; cf. Thellung 1926; it is uncertain to which of these taxa the lectotype of P. sativa belongs). According to Loos (1993) the tuberous morphotype is large, early-flowering, and has umbels with many umbellules, while the non-tuberous morphotype is medium-sized, late-flowering, and has umbels with fewer umbellules. The Nordic material may be subdivided into two entities based on these characters. The tuberous morphotype also tends to have a softer stem and broader, more coarsely serrate leaflets, but a large portion of the herbarium material is too poor for a reliable determination. Both morphotypes can be either hairy or glabrous, but most specimens with long and wavy hairs are probably non-tuberous. Also Loos (1993) reported hairy morphotypes within both entities. Plant size and number of umbellules are modifiable, and leaflet shape is dependent on the position of the leaf (lower leaves having wider leaflets), which makes it difficult to identify the taxa. Mainly for practical reasons (insufficient distributional data), they are not separated here. However, the non-tuberous morphotype seems to be the most common one.

Some specimens (S Sk, Upl) have bipinnate leaves with rather narrow lobes, and a ± lobed stylopodium. They have been called var. fleischmannii (Hladnik ex W.D.J. Koch) Burnat, and have even been treated at specific level (Reduron 2008). This morphotype, found once in the wild, was grown in the botanic garden of Ljubljana and spread as a cultivar; it is here regarded as an aberration without taxonomical significance. It seems to cross freely with normal P. sativa (intermediates in S Upl).