Plants of South Eastern New South Wales

Senecio linearifolius

Flowering branches (var. arachnoideus) Photographer Max Campbell, Brogo

Back of leaf (var. arachnoideus) Photographer Steve Burrows, Pambula Beach

Flower heads and leaves (var. latifolius). Australian Plant Image Index, photographer Murray Fagg, Kosciuszko National Park

Flowering branches (var. denticulatus) Photographer Steve Burrows, Bournda National Park south of Tathra

Back of leaf (var. denticulatus) Photographer Steve Burrows, Bournda National Park south of Tathra

Common name

Fireweed groundsel, Fireweed

Family

Asteraceae

Where found

Forest, woodland, and coastal shrubland. Widespread.

Var. arachnoideus:   Forest and coastal shrubland. Widespread. No records from the Western Slopes west and north of the Hume Highway.

Var. denticulatus:  Forest. Coastal south from Mimosa Rocks National Park north of Tathra. ACT. One record from near the Snowy Mountains Highway south east of Nimmitabel.

Var. intermedius: Forest and woodland. Mostly ACT and nearby. Scattered records elsewhere.

Var. latifolius: Forest and woodland, usually at altitudes over 1000 m.  Kosciuszko National Park and the mountains west of Kosciuszko National Park towards Albury. ACT. Tablelands and ranges south of the Hume Highway.

Var. macrodontus: Forest and woodland. Coast and ranges north from Jervis Bay. Occasionally elsewhere.

Notes

Perennial herb or shrub to about 1.5 m high. Leaves aromatic when rubbed. Stems hairless to cobwebby, sometimes glaucous. Leaves alternating up the stems. Leaves in the middle to upper third of the stems 2-20 cm long, 1-50 mm wide, margins entire to toothed. Flower heads with 4–8 'petals' each 3-8 mm long, and yellow centres 1.5-3 mm in diameter with 4–21 florets. Flower heads behind the ‘petals’ cylindrical to weakly bell-shaped, surrounded by 7-13 appressed green bracts. Flower heads in 20–200 or more flowered clusters. Flowering: throughout the year.

var. arachnoideus:  Plants not glaucous. Immature stems and leaves more or less densely woolly at first. Underside of mature leaves slightly to moderately obscured by tangled wispy hairs. Upper leaves narrow, length:width ratio 4.5-12, margins usually toothed. Flower heads behind the 'petals' 3.5-4.5 mm long, 1.5-2.5 mm in diameter. 'Petals' 5-8. Florets in the centre of the flower heads 10-20. Appressed bracts surrounding the flower heads 9-13.

var. denticulatus:  Plants not glaucous. Leaves to 20 mm wide, upper leaves narrow, length:width ratio 4-15, lower surface hairless or cobwebby (the surface only moderately obscured), margins toothed, teeth frequency 1–3 per cm, bases with prominent auricles consisting of segments almost discontinuous with the leaf blade. Flower heads behind the 'petals' 2.5-4 mm long, 1.5-2 mm in diameter. 'Petals' 4-8. Florets in the centre of the flower heads 4-18. Appressed bracts surrounding the flower heads 7-11.

All native plants on unleased land in the ACT are protected.

var. intermedius:  Plants slightly glaucous at least on newer growth, almost hairless. Upper leaves narrow, to 12 cm long, length:width ratio 6-30, lower surface usually glaucous with weak, coarse, spreading hairs, margins entire to toothed. Flower heads behind the 'petals' 3-4 mm long, 1.6-2.5 mm in diameter, overall 6-10 mm in diameter, at least in the ACT. 'Petals' 4-8. Florets in the centre of the flower heads 7-18. Appressed bracts surrounding the flower heads 8-12.

All native plants on unleased land in the ACT are protected.

Rare Vic.

var. latifolius:  Plants not glaucous. Upper leaves narrow, to 14 cm long, length:width ratio 1.5-6, lower surface hairless or nearly so, rarely cobwebby, margins toothed. Leaf width to 50 mm wide, 7-33 mm wide in the ACT. Flower heads behind the 'petals' 2.5-4.5 mm long, 1.0-1.6 mm in diameter. 'Petals' 4-5. Florets in the centre of the flower heads 7-15. Appressed bracts surrounding the flower heads 8-11.

All native plants on unleased land in the ACT are protected.

var. macrodontus:  Plants slightly to moderately glaucous. Lower surface of the leaves usually sparsely hairy, with hairs coarse-based and spreading, margins toothed, teeth frequency 3–5. Upper leaves narrow, length:width ratio 5-8. Flower heads behind the 'petals' 4.5-5.5 mm long, 1.8-2.8 mm in diameter. 'Petals' mostly 5-8. Florets in the centre of the flower heads 9-21. Appressed bracts surrounding the flower heads mostly 9-12.

PlantNET description of species:  http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Senecio~linearifolius (accessed 6 February, 2021)