Gnaphalium L.

Volume IV (1988) - Flora of New Zealand Naturalised Pteridophytes, Gymnosperms, Dicotyledons

GNAPHALIUM L.

Herbs, rarely woody at base. Lvs alternate, simple, entire. Capitula solitary or in small to large clusters; clusters usually capitate or forming spikes, rarely forming panicles. Involucral bracts in 2-several rows, imbricate, membranous, sometimes with coloured but not radiating lamina. Receptacle ± flat; scales 0. Outer florets ♀, filiform, usually many. Inner florets ⚥, tubular, few. Achenes all similar, ± terete, not angled or ribbed; pappus hairs in 1 row, narrow at apex.

Key

Capitula in terminal or axillary leafy clusters; clusters usually coalescing to form terminal spikes, or rarely panicles; annuals or biennials, lacking stolons

Capitula solitary or 2-numerous in a terminal cluster subtended by a leafy involucre, sometimes with discrete clusters below; stoloniferous perennials (except G. sphaericum, annual and lacking stolons)

Lvs ± concolorous; basal lvs usually 0 at flowering, sometimes present and withered

Lvs somewhat to strongly discolorous; basal lvs often present at flowering, sometimes dead but persistent, sometimes 0

Involucral bracts 3-4 mm long; lvs silky hairy

Involucral bracts 2-3 mm long; lvs tomentose

Involucral bracts usually bright reddish purple in bud; lower cauline lvs usually plane; stems branched only at base with usually dense terminal spikes and often scattered clusters below

7. *subfalcatum

Involucral bracts usually not coloured in bud, rarely flushed reddish purple; lower cauline lvs folded or plane; stems usually much branched at base and above forming paniculate infls and terminal spikes

2. *calviceps

Plants much-branched from base; involucral bracts 2-2.5 mm long; pappus hairs free at base

*uliginosum ζ

Plants with 1-few stems; involucral bracts 2.5-3 mm long; pappus hairs connate at base

4. *pensylvanicum

Lvs glabrous and shiny on upper surface, or sparsely hairy when young

Lvs sparsely to moderately tomentose and dull on upper surface

Involucral bracts 3.5-4.2 mm long, apiculate and spreading at apex

1. *americanum

Involucral bracts 2.5-3.2 mm long, acute to apiculate and erect at apex

3. *coarctatum

Plant 40-120 cm tall, usually single-stemmed; clusters of capitula often remaining discrete and infl. conspicuously leafy

6. *simplicicaule

Plant 8-50 cm tall, often with several stems; clusters mostly forming terminal spikes, and discrete below, subtended by short lvs

Involucral bracts 4-4.5 mm long; achenes 0.6-0.8 mm long

5 *purpureum

Involucral bracts 2.5-3 mm long; achenes 0.4-0.5 mm long

4. *pensylvanicum

Capitula (1)-2-numerous in usually dense or rarely somewhat diffuse clusters

Capitula all or mostly solitary

Annual, lacking stolons; capitula c. 1 mm diam., numerous in dense terminal clusters, very rarely a few axillary clusters below; ⚥ florets 1 per capitulum

20 sphaericum

Perennial, stoloniferous; capitula 1-3 mm diam., (1)-2-numerous in dense or somewhat diffuse terminal clusters and with sometimes axillary clusters below; ⚥ florets > 2 per capitulum

Terminal clusters with (1)-2-9 capitula; flowering stems lateral

Terminal clusters with (5)-8-numerous capitula; flowering stems lateral or terminal

Basal lvs usually long-petiolate, elliptic-oblanceolate to oblanceolate; involucral bracts (3)-3.5-4 mm long; achenes minutely papillate

9. delicatum

Basal lvs short-petiolate, narrow-elliptic to ± linear; involucral bracts 4.2-5 mm long; achenes with short antrorse hairs

10. ensifer

Mature lvs glabrous on upper surface, sometimes sparsely to moderately tomentose when young

Mature lvs sparsely to densely tomentose on upper surface

Flowering stems all lateral; lvs mostly basal at flowering; rosettes forming leafy patches

11. gymnocephalum

Flowering stems terminal, or lateral and terminal; lvs mostly cauline at flowering, the rosette lvs usually 0 or withered; rosettes growing singly or a few together but not forming leafy patches

Mature achenes minutely papillate; cauline lvs 30-200 mm long, ascending; capitula 1.5-3 mm diam.

12 involucratum

Mature achenes glabrous; cauline lvs 15-50-(80) mm long, spreading; capitula 1-2 mm diam.

14 limosum

Basal lvs 3-19 cm long, usually long-petiolate, usually glabrous, at most moderately hairy on upper surface when young

11. gymnocephalum

Basal lvs 0.5-5-(10) cm long, short-petiolate, sparsely to densely hairy on upper surface

Cauline lvs usually much reduced upwards to infl.; basal lvs narrow- to broad-obovate or oblanceolate, usually obtuse, sometimes acute; involucral bract lamina yellow to pale brown or orange

8. audax

Cauline lvs scarcely reduced upwards to infl.; basal lvs narrow-obovate or oblanceolate, acute; involucral bract lamina mid to dark brown

19 ruahinicum

Achenes glabrous; flowering stem terminal to leafy rosette; plant usually mat-forming

Achenes hairy or sparsely papillate; flowering stems 1-3 and lateral to leafy rosette; plants growing singly or forming loose patches

Lvs with fine, matted, white tomentum; involucral bracts 4.5-6 mm long; capitula c. 2-4 mm diam.; lvs elliptic to broad-elliptic or spathulate

15 mackayi

Lvs with straight, separate, silky hairs; involucral bracts 7-7.5 mm long; capitula c. 5-8 mm diam.; lvs narrow-oblong to spathulate

16 nitidulum

Capitula c. 4-6 mm diam.; involucral bracts 5.5-6.5 mm long; lvs always moderately to densely tomentose on upper surface

21 traversii

Capitula c. 1-3 mm diam.; involucral bracts 3-5.2 mm long; lvs glabrous or sparsely to densely tomentose on upper surface

Lvs usually densely, sometimes moderately tomentose on upper surface; involucral bracts 4-5.2 mm long; capitula (1.5) -2-3 mm diam.

13 laterale

Lvs usually glabrous on upper surface, rarely sparsely tomentose; involucral bracts 3-4.5 mm long; capitula c. 1-2 mm diam.

Lvs glabrous and folded or moderately tomentose and plane on upper surface, 0.5-2-(4) mm broad; ⚥ florets 1-3-(5); involucral bracts 3.8-4.5 mm long

17 paludosum

Lvs usually plane and glabrous or sparsely tomentose on upper surface, rarely glabrous and folded, (1)-2-4-(5) mm broad; ⚥ florets (2)-4-7; involucral bracts 3.2-4-(4.5) mm long

18 polylepis

c. 150 spp., cosmopolitan. Native spp. 14, naturalised 8.

Gnaphalium has long been considered rather a heterogeneous assemblage of spp., and Drury (1970, op. cit.), in providing a fresh approach to its classification, recognised 3 main groups based mainly on the form of the involucral bracts (Fig. 26) - of these, the native spp. treated by him as anaphalioid cudweeds have been transferred to Anaphalis (Webb, in Connor and Edgar, op. cit.), while the sp. previously known as G. candidissimum is treated in Vellereophyton (Hilliard and Burtt, op. cit.); G. luteoalbum, classified by Drury as an achyroclinoid cudweed is treated within a broader concept of Pseudognaphalium Kirpiczn. (Hilliard and Burtt, op. cit.). Within the remaining group, the gnaphalioid cudweeds, Drury recognised 4 sections and these are sometimes treated at generic level. The indigenous spp. all fall within sect. Euchiton, the naturalised American spp. within sect. Gamochaeta, and G. uliginosum within sect. Gnaphalium.

Drury, D. G., New Zealand J. Bot. 9 : 157-185 (1971), revised the American spicate cudweeds naturalised in N.Z. He distinguished 8 spp., several of them known from only a few collections, and provided illustrations for all of them. All of these taxa are accepted here, but one only at varietal rank. Of these, G. coarctatum is by far the most common and widespread. Allan (1961) accepted 10 spp. of Gnaphalium indigenous to N.Z.; of these 4 are referred here to Anaphalis, and 1 to Pseudognaphalium. The remaining spp., all in sect. Euchiton, were revised by Drury, D. G., New Zealand J. Bot. 10 : 112-179 (1972), who accepted 11 spp. All of Drury's spp. are accepted here and in addition 2 entities he treated at an infraspecific level are accepted here as full spp. Plant habit, lf shape and hairiness, involucral bract length, and achene hairs are all important characters for identification and Drury provided clear illustrations for most spp. Drury also provided ⚥ and ♀ floret numbers which may help to discriminate spp. In spite of the excellent work of Drury, difficulties remain within sect. Euchiton in N.Z. At the end of his revision he gave descriptions and listed collections for 3 sets (" examples") of plants of uncertain status. Plants of his examples 1 and 2 are referred by A. P. Druce to G. delicatum and G. audax sens. strict. respectively, and plants corresponding to example 3 are now treated as a new sp., G. laterale. Other particular difficulties are discussed under G. involucratum and G. limosum.

Descriptions of the involucral bracts for both the naturalised spp. of sect. Gamochaeta and the indigenous spp. in sect. Euchiton are based on the largest, fully developed bracts of capitula at anthesis.

Fig. 26. Gnaphalium and related genera, middle involucral bracts. A Anaphalis trinervis; B Pseudognaphalium luteoalbum; C Gnaphalium delicatum. © All rights reserved. [Image: 4X4I]

Gnaphalium L.

Key

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