Print Fact SheetPraxelis clematidea

Taxonomy

Praxelis clematidea (Griseb.) R.M.King & H.Rob., Phytologia 20: 194. 1970.

Common synonyms

Eupatorium clematideum Griseb. Abh. Königl. Ges. Wiss. Göttingen 19: 172. 1879.

Common name

Praxelis

Description

Propagule or dispersal unit is the fruit. Fertile part 2-3 mm long, 0.3-0.8 mm wide, in side view widest in upper part (obovoid), +/- straight, the upper (apical) end narrowing or suddenly cut off (truncate), in cross-section flattened or angular (prismatic), basal scar (carpopodium) pronounced and well-differentiated, off to the side (oblique) or at least asymmetric, beak (=thinner sterile stalk between seed and pappus) absent, wings absent, fruit surface black, smooth (except at cellular level), with simple straight hairs, thickened margin absent, longitudinal ribs present, 3-4, their surfaces smooth, with simple straight hairs.

Pappus type bristles / hairs, pappus elements all +/- similar, up to 3.5-5 mm long, in one row, pappus elements numerous, persistent, the individual bristles rough / serrated (barbellate), +/- equal width along length, white / translucent or brown.

Ecology

Annual to short-lived perennial herb, fruits wind-dispersed. Tropical to subtropical areas. Rapidly colonises after fire and able to tolerate various soil types. Found on rail- and roadsides, fencelines, riverbanks, over-grazed pastures, but also relatively undisturbed grasslands, woodlands and conservation areas.

Native range

Venezuela, Brazil, Bolivia, Argentina.

Introduced range

United States (Florida), China, Taiwan, Papua New Guinea, Australia.

Weed status within Australia

WA Declared Pest s12 (C1, C2 Prohibited).

Past interceptions (Australia): origins

Canada, China, Thailand, Vietnam, Fiji.

Past interceptions (Australia): commodities

Wooden boxes, new tyres, containers, new vehicles, machinery, fresh fruit, cardboard packaging.