Ageratina riparia
Common name
mist flower
Family
Asteraceae
Flora category
Vascular – Exotic
Structural class
Herbs - Dicotyledonous composites
NVS code
The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.
AGERIP
Habitat
Terrestrial. Humid subtropical and tropical rainforests (W.T. Parsons & E.G. Cuthbertson 2001). In NZ, coastal, lowland (Timmins & MacKenzie 1995). Forest margin, damp banks and streamsides, slips (Timmins & MacKenzie 1995). In Australia, shaded riverbanks, steep south facing hillsides in areas where annual rainfall exceeds 1700mm (W.T. Parsons & E.G. Cuthbertson 2001).
Features
Erect or sprawling, many-stemmed herb to subshrub to 0.5-1.5 m. Perennial fibrous rootstock. Stems occ die back in winter, covered in purple-striped non-sticky hairs, usually purple, becoming woody, with branches in opposite pairs. Leaves in opposite pairs, 60-100 x 15-25 mm, willow-like, coarsely serrate except near base. Flowers small, white, 4-5 mm diam, in terminal clusters, Aug-Jan. Seeds black, 5-angled, 2 mm long.
Similar taxa
Distinctive toothed leaves separate mistflower from Mexican devil
Flowering
August, September, October, November, December, January, February, March
Flower colours
White
Fruiting
June-September (W.T. Parsons & E.G. Cuthbertson 2001)
Year naturalised
1931
Origin
Mexico, W. Indies
Etymology
riparia: From the Latin ripa ‘streambank or ‘riverbank’ and the suffix -aris which gives the sense ‘belonging to’ or ’ resembling’. Riparia means growing on the banks of streams or rivers
Reason For Introduction
Ornamental
Life Cycle Comments
Perennial.
Reproduction
Reproduces by seed. Plants may re-grow following disturbance if roots (occasionally stems) contact ground. Drooping stems can layer in wet sites.
Seed
Many seeds produced.
Dispersal
wind, water, road mowing machines (Timmins & MacKenzie 1995).
Tolerances
Tolerant of deep shade and damp, damage and grazing, salt, most soils