Senecio family - Ragworts and Groundsels

Senecio was split into Senecio and Jacobea on clear genetic grounds, but there are few consistent morphological differences.

Jacobaea vulgaris (Senecio jacobaea) Common Ragwort Erect perennial to 1.5m with herbaceous, grooved stem ±with web-like hairs, but no glandular hairs. Basal leaves ovate to obovate, ±pinnatifid with blunt basal lobe no wider than the other lobes. Normally dying before flowering complete. Leaves ±hairy underneath mainly on veins and no glandular hairs. Stem leaves pinnatifid with blunt basal lobe not wider than the rest of the leaf. Dense inflorescence with overlapping flowers. Supplementary phyllaries 1/4 as long as the main ones. Achenes are hairy

Senecio squalidus – Oxford Ragwort Stems ±woody at the base to 50cms. Stem and leaves ±glabrous. Leaves deeply pinnately lobed to only serrate with terminal lobe acutely pointed. Lower leaves petiolate and upper leaves are sessile. All phyllaries are black tipped. Flowers 16-20mm in open inflorescence. Derived from a hybrid and shows variability.

Jacobaea aquatica (Senecio aquaticus) Marsh Ragwort has1 - 2 pairs of lateral lobes and terminal lobe is much larger. Supplementary phyllaries 1/4 as long as the main ones and tend to be brown tipped. Lax flowerhead. Achenes of disc flowers are ±glabrous

Senecio inaequidens – Narrow-leafed Ragwort Stems woody at the base to 80cms. Stem and leaves ±glabrous. Upper and middle leaves are linear ±entire, sessile and < 5mm wide. ±small teeth ± in-rolled. Yellow narrow petals. in an open inflorescence.

Senecio vulgaris – Groundsel has pinnatifid leaves, ±cottony or downy below. Lower leaves petiolate, upper leaves sessile ±clasping. No glandular hairs.

Heads 4-5mm across sessile initially later stalked. Involucre cylindrical.

Outer and inner phyllaries ±black-tipped. Ray florets if present < 5mm, revolute. Achenes <2.5mm and are appressed hairy between ribs

ssp. vulgaris is the usual one with no ligules (ray florets). Widespread, gardens, waste ground, streets flowers all the year

var. hibernicus has revolute ligules

(ssp. denticulatus has revolute ligules, unbranched stem lots of web-like hairs, less lobed leaves, fewer capitula and is found in dunes)

Senecio sylvaticus– Heath Groundsel Tall annual to 70cm. Like S. viscosus but less hairy and ±not sticky. Glandular hairs at least on the peduncles. Leaves like S. vulgaris but even more strongly pinnatifid. Supplementary (outer) phyllaries <1/4 as long as the main ones. Phyllary tips are usually green. Ligules < 6mm strongly revolute. Flowers similar in size to S. vulgaris. Achenes are minutely hairy all over. Sandy soils, cliffs, heaths and roadsides

Senecio viscosus – Sticky Groundsel Annual to 60cm. Leaves like S. vulgaris but even more strongly pinnatifid, lower leaves petiolate, upper leaves sessile. Sticky glands (glandular hairs) on stem and leaves, so looks greyish (covered in dirt and dust under lens). Supplementary (outer) phyllaries 1/3 -1/2 as long as the main ones. Phyllary tips are green or brownish/black. Ligules 8 - 15, < 8mm becoming strongly revolute. Flowers larger than S. vulgaris. Achenes glabrous or just minutely hairy in the grooves Similar places to Groundsel but later in the season

Jacobaea erucifolia (Senecio erucifolius) Hoary Ragwort Like J. vulgaris but densely hairy when with non-glandular hairs later leaves are grey-hairy on the underside. Leaves deeply pinnatifid, often in-rolled and lowest lobes clasp the stem. Supplementary phyllaries 1/2 as long as the main ones. Achenes hairy on ribs

Senecio sarracenicus Broad-leaved Ragwort Erect perennial to 1.5m leaves are unlobed, lanceolate. Middle and upper stem leaves are sessile, ± clasping, mid rib raised below and pale and prominent on top, leaves have teeth with an incurved apex, can be cartilaginous.

Neophyte usually in large stands beside water