Equisetum arvense
Common name
Horsetail
Family
Equisetaceae
Flora category
Vascular – Exotic
Structural class
Ferns
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.
EQUARV
Habitat
Terrestrial. Bare land, riversystems especially silty, sandy and gravely sites, streambanks.
Features
Erect, colony-forming, summer-green perennial, primitive fern-ally to 10-80 cm. All aerial parts die back in winter. Extensive, deep, freely branching rhizomes with round tubers. Stems of 2 types. Sterile stems green, 10-80 cm long, 1-5 mm diam, jointed, hollow, ribbed or grooved, very rough to touch (containing silica), with lateral branches in whorls; leaves are 10 mm green sheaths. Resembles pine seedling. Fertile stems pale brown, shorter, joints larger, unbranched, with pale brown 14 mm sheaths; producing terminal cones; appearing in early spring before sterile stems and dying quickly after shedding spores. Cones conspicuous, 4-40 mm long. Spores seldom produced in NZ.
Similar taxa
Equisetum hyemale rough horsetail is very similar but rare; has slender, taller, very rough, asparagus-like spears with black rings, no leaves, no (occ few small) branches, cones on green stems. E. fluviatile (rare).
Flowering
N/A
Flower colours
No flowers
Year naturalised
1922
Origin
N temperate
Etymology
equisetum: From the Latin equus ‘horse’ and setum ‘bristle’, the barren growths resembling horses’ tails.
arvense: Growing in arable fields
Reason For Introduction
Accidental.
Life Cycle Comments
Perennial
Reproduction
Reproducing by spores instead of seeds, and by rhizomes, to which are attached small tubers. (Wax, Fawcett, Isley eds. 1981). Fruiting heads contain masses of tiny pale greenish spores in small pine-cone like structure. Stems tough and wiry, hollow, jointed, and of two types: fertile, producing fruiting heads and having large, easily separable joints, not branched; Sterile or vegetative, having much smaller joints, with lateral branches in whorls around the main stem. Leaves on sterile stems only, in the form of cup shaped toothed sheaths at the joints (Wax, Fawcett, Isley eds. 1981).
Plant is dispersed by river systems, soil movement, humans (popular with herbalists).