Japanese Cudweed

Gnaphalium sphaericum Willd.

Family: - Asteraceae.

Names:

Japanese Cudweed.

Other names:

Common Cudweed

Creeping Cudweed

Cudweed.

Summary:

A white-woolly stemmed, annual to perennial herb, to 700 mm tall, with brown to red-purple, clustered flower heads.

Description:

Cotyledons:

Two. Very small, round, 1mm diameter. Fine hairs. Tip round.

First leaves:

Narrowly club shaped. Downy hairs. Pointed tip.

Leaves:

Basal and along the stems.

Petiole - None or a short narrow one.

Blade - Basal leaves oval, egg shaped, spade shaped or almost parallel sided. 10-150 mm long, stiff, dark green on top white underneath. Becoming hairless with age on the upper surface, white woolly hairs underneath. Tip rounded with a short sharp flexible point. Wavy edge especially near the base.

Stem leaves - alternate, smaller, parallel sided, stiff, dark green on top white underneath. Edges rolled inwards on the lower surface. Becoming hairless with age on the upper surface, white woolly hairs underneath. Tip rounded with a short sharp flexible point merging into the floral leaves.

Stems:

One to several, erect, 30-700 mm tall. Furry white with long loosely matted hair.

Flower head:

Dense, globular, stalkless cluster on the ends of stems, 8-25 mm diameter. Made up of partial heads, 3-4 mm long on short stalks (pedicel). Bracts with yellow to brownish with a green base and shiny with blunt tips. Inner bracts are longer and narrower than the outer ones. 5-8, long, floral leaves underneath the flower head.

Flowers:

Florets - Reddish purple, No 'petals'. In groups of 16-20 female and 1 bisexual flower.

Ovary -

Stamens -

Anthers -

Fruit:

Achene, 0.5 mm long, oblong with sparse tiny hairs. Pappus with 8-12 rough, fine, free, persistent, bristles.

Seeds:

Tiny, oblong.

Roots:

Key Characters:

Flower heads in dense terminal clusters with 5-8 long floral leaves underneath. 16-20 female and 1 bisexual floret in each head. Pappus bristles free to the base and persistent.

Biology:

Life cycle:

Annual or perennial. Seeds germinate in autumn and winter and it grows mainly in winter and spring. Most of the flowering occurs between July and December.

Physiology:

Reproduction:

By seed.

Flowering times:

Late winter to spring in Western NSW.

Seed Biology and Germination:

Vegetative Propagules:

None.

Hybrids:

Allelopathy:

Population Dynamics and Dispersal:

Tends to occur as scattered plants with occasional dense patches forming in some years.

Origin and History:

Australia.

Distribution:

NSW, SA, VIC, WA.

Habitats:

Climate:

Temperate.

Soil:

Wide range.

Plant Associations:

Many.

Significance:

Beneficial:

Fodder of low value. Occasionally grazed.

Detrimental:

Weed of crops, lawns, roadsides, pastures and disturbed areas.

Toxicity:

Not recorded as toxic.

Legislation:

None.

Management and Control:

Thresholds:

Eradication strategies:

Herbicide resistance:

Biological Control:

Related plants:

Spiked Cudweed (G. spicatum)

Western Cudweed (G. polycaulon)

(G. subfalcatum)

Plants of similar appearance:

Jersey Cudweed (Pseudognaphalium luteo-album)

References:

Auld, B.A. and Medd R.W. (1992). Weeds. An illustrated botanical guide to the weeds of Australia. (Inkata Press, Melbourne). P103. Photo.

Cunningham, G.M., Mulham, W.E., Milthorpe, P.L. and Leigh, J.H. (1992). Plants of Western New South Wales. (Inkata Press, Melbourne). P686. Photo.

Lamp, C. and Collet, F. (1990). A Field Guide to Weeds in Australia. (Inkata Press, Melbourne).

Lazarides, M. and Hince, B. (1993). CSIRO handbook of economic plants of Australia. (CSIRO, Melbourne). #595.4.

Marchant, N.G., Wheeler, J.R., Rye, B.L., Bennett, E.M., Lander, N.S. and Macfarlane, T.D. (1987). Flora of the Perth Region. (Western Australian Herbarium, Department of Agriculture, Western Australia). P680-681

Wilding, J.L. et al. (1987). Crop weeds. (Inkata Press, Melbourne). P54. Diagrams. Photos.

Acknowledgments:

Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information.