Cyanthillium cinereum
(little ironweed)

Preferred Scientific Name

• Cyanthillium cinereum (L.) H. Rob

Preferred Common Name

• little ironweed

Other Scientific Names

• Blumea esquirolii H.Lev. & Vaniot
• Cacalia arguta Kuntze
• Cacalia cinerea (L.) Kuntze
• Cacalia erigerodes Kuntze
• Cacalia exilis Kuntze
• Cacalia kroneana Kuntze
• Cacalia linfolia DC.
• Cacalia rotundifolia Willd.
• Cacalia vialis Kuntze
• Calea cordata Lour.
• Cineraria glaberrima Spreng. ex DC.
• Conyza chinensis L.
• Conyza cinerea L.
• Conzya heterophylla Lam.
• Conzya incana DC.
• Conzya prolifera Lam.
• Crassocephalum flatmense Hochst. & Steud. ex DC.
• Cyanopis decurrens Zoll. & Mor.
• Eupatorium arboreum Reinw. ex de Vriese
• Eupatorium myosotifolium Jacq.
• Pteronia tomentosa Lour.
• Seneciodes cinereum (L.) Kuntze
• Serratula cinerea (L.) Roxb.
• Vernonia abbreviata DC.
• Vernonia arguta Baker
• Vernonia betonicaefolia Baker
• Vernonia cinerea (L.) Less.
• Vernonia exilis Miq.
• Vernonia fasciculata Blume
• Vernonia kroneana Miq.
• Vernonia vialis DC.

International Common Names

• English: ironweed; small ironweed; vernonia
• Spanish: machadita; rabo de buey; yerba morada
• French: ayapana sauvage
• Chinese: ye xiang niu

Local Common Names

• Cuba: machadita
• Fiji: kaukamea; tho vuka; vutikaumondro
• India: ankari; ankta; pokasubgo; sahaderi; sandri
• Indonesia: maryuna
• Japan: mura-saki-mukashi-yomogi; reinan-nogiku; yambaru-higotai
• Lesser Antilles: inflammation bush; iron bush; measle bush
• Malaysia: rumput taki babi; tambak-tambak
• Mauritius: ayapa sauvage
• Nigeria: bojure
• Philippines: agas-moro; bulak-manok; kolong-kugon
• Puerto Rico: rabo de buey; yerba socialista
• Sri Lanka: alavangu pillu; monara kudumbiya
• Thailand: kaan thuup; yaa dok khaao; yaa-saam-wan; ya-la-ong

• Domain: Eukaryota
•     Kingdom: Plantae
•         Phylum: Spermatophyta
•             Subphylum: Angiospermae
•                 Class: Dicotyledonae
•                     Order: Asterales
•                         Family: Asteraceae
•                             Genus: Cyanthillium
•                                 Species: Cyanthillium cinereum

The family Asteraceae is one of the most diverse groups among flowering plants including 1620 genera and about 23,600 species (Stevens, 2012). Species in the Asteraceae are very variable vegetatively, but may be recognized by their “capitulate” and involucrate inflorescences in which numerous small flowers open first on the outside and are infrequently subtended by bracts. The anthers in this family are usually fused and form a tube through which the style extends before the two stigmatic lobes separate and become recurved. The rather small, single-seeded fruits usually have a plumose “pappus” and are frequently dispersed by wind (Stevens, 2012).

The genus Cyanthillium has been used as a synonym of Vernonia, while other botanists have treated both genera as distinct. Currently, both genera are treated separately and Cyanthillium is distinguished from Vernonia by its smooth to finely 5-striate (vs. 5-10-ribbed) achenes, and by its echinolophate (vs. tricolporate) pollen, and by base chromosome number usually reported as 2n = 18 or 20 (vs. 2n = 34). Currently five species are recognized within Cyanthillium (Funk and Pruski, 1996).

Annual herb, to 80 (-150) cm tall. Stems unbranched or more commonly few-branched. Leaves petiolate or distal ones sessile; petioles to 1.5 cm, narrowly winged; blade 1.5-5 × 1-1.5(4) cm, obovate or less often elliptic or ovate, base cuneate, apex acute to obtuse, lower surface pilose, usually glandular. Inflorescence of 5 to numerous heads, 13-20-flowered; involucre 2.5-3 mm long; outer phyllaries much reduced, inner phyllaries subequal. Corolla 3-4 mm, exserted 1.5-2 mm from involucre, the tube long and narrow, 2-3 mm, the limbs short, pilose. Achenes 1.2–2 mm long, subfusiform, terete not ribbed, inner pappus white, exserted from involucre and nearly as long as the corollas (Funk and Pruski, 1996).

The history of introduction of C. cinereum is uncertain. It is highly probable that the species has been introduced accidentally as a contaminant or as a weed in nursery materials (Holm et al., 1997). For the West Indies, herbarium collections show that it was first collected in Jamaica in 1882 (US Herbarium Collection). In Central America the date of introduction is unclear but since the 1950s the species appears listed as a weed (Cardenas and Coulston, 1967).

Soil drainage

• free

Soil reaction

• acid
• neutral

Soil texture

• heavy
• light
• medium

Special soil tolerances

• saline

C. cinereum spreads by seeds which are adapted to wind dispersal. In addition, seeds may be secondarily dispersed as a contaminant in crop seeds, pasture seeds and in agricultural machinery (Holm et al., 1997; Pruski 2013).

C. cinereum is a weed with important economic impacts mainly in agriculture, pasture and garden activities. It is listed as a weed in about 27 different crops in 47 countries in Asia, Australia, Africa and America. In addition, C. cinereum has the potential to negatively impact natural and seminatural habitats in coastal areas, forest edges, secondary forests, upland forests, and grasslands (Pruski, 2013).

C. cinereum can host the tobacco leaf curl virus and the root-knot nematode (Holm et al., 1997).

• Invasive in its native range
• Proved invasive outside its native range
• Has a broad native range
• Abundant in its native range
• Highly adaptable to different environments
• Is a habitat generalist
• Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc
• Pioneering in disturbed areas
• Highly mobile locally
• Benefits from human association (i.e. it is a human commensal)
• Fast growing

• Damaged ecosystem services
• Ecosystem change/ habitat alteration
• Loss of medicinal resources
• Modification of successional patterns
• Monoculture formation
• Negatively impacts agriculture
• Negatively impacts cultural/traditional practices
• Negatively impacts forestry

• Competition - monopolizing resources
• Pest and disease transmission
• Rapid growth

• Highly likely to be transported internationally accidentally
• Difficult to identify/detect as a commodity contaminant
• Difficult/costly to control

Leaves of C. cinereum have some antibiotic activity and consequently they are frequently used in traditional medicine in India to treat conjunctivitis, dropsy and urinary disorders. In the Philippines, this species is used as an infusion for cough and skin diseases. A poultice from leaves reduces headaches while a root decoction relieves stomach aches and diarrhea. In Thailand, the leaves are used in the treatment of asthma and bronchitis (Holm et al., 1997; PROTA4U, 2013). The young shoots are eaten as a cooked vegetable in Java (PROTA4U, 2013).