Helichrysum Miller

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1976, Flora Europaea. Volume 4. Plantaginaceae to Compositae (and Rubiaceae), Cambridge University Press : 128

24. Helichrysum Miller 2

Herbs or dwarf shrubs, often lanate or tomentose. Leaves alternate, simple, entire. Capitula small to medium, solitary or aggregated into compound corymbs. Involucre cylindricalcampanulate to hemispherical; involucral bracts numerous, imbricate, scarious, white or coloured at least distally. Florets yellow, all tubular, the outer usually female, the inner hermaphrodite, more numerous; rarely all hermaphrodite. Pappus of scabrid or shortly plumose hairs.

The distinction from Gnaphalium , in which female florets outnumber the hermaphrodite, is not clear-cut.

1 Involucre about equalling the florets, remaining erect or nearly so throughout anthesis

2 All or most of the leaves with revolute margins

3Herbaceous perennial; upper leaves narrowly linear 13. arenarium

3 Dwarf shrub (5-10). stoechas group

2 All or most of the leaves flat, their margins not revolute

4 Involucre 7-10 mm in diameter 11. orientale

4 Involucre 4-5 mm in diameter

5 Stem and leaves densely glandular 12. plicatum

5 Stem and leaves eglandular

6 Indumentum of leaves and stems appressed-tomentose, greyish-white; all florets hermaphrodite 13. arenarium

6 Indumentum often yellowish-green, sparsely to densely villous-lanate; outer florets female 14. graveolens

1 Involucre greatly exceeding the florets, becoming patent

7 Annual or biennial herb

8Cauline leaves sessile, amplexicaul, white-tomentose beneath; capitula clustered 15. foetidum

8 Cauline leaves shortly petiolate, green beneath; capitula solitary 16. bracteatum

7 Caespitose or woody perennial

9 Involucre yellow 11. orientale

9Involucre white

10 Leaves not more than 5 mm, all linear-oblong, closely imbricate 4. frigidum

10 Some leaves more than 15 mm, oblong-spathulate to narrowly oblanceolate

11 Flowering stems 10-30 cm; capitula at least 5 1. amorginum

11 Flowering stems 5-10 cm; capitula 1-4

12 Rosette-leaves and lower cauline leaves 15-60x5-10

mm 2. sibthorpii

12 Rosette-leaves 5-10(-15)mm; lower cauline leaves 20-30x2-4 mm 3. doerfleri