Cytisus: From the Greek kytisos 'trefoil', referring to the shape of the leaves of many species
Vascular - Exotic
Terrestrial. A plant of lowland and montane habitats. Plant occurs in sites with low-moderate-high fertility. The plant normally grows in areas of high rainfall, on acid soils but never on chalks. Plant grows in shrubland, tall tussockland, short tussockland, cliff, bluff and riverbed communities (Timmins & MacKenzie 1995). The plant grows in disturbed lowland and montane habits such as pasture, waste ground, riverbeds and poorly grazed areas.
Much-branched deciduous shrub up to 2m high; twigs glabrous, but sericeous when young, green, more or less 5-angled. Leaves variable, usually glabrous above and sericeous below, and 3-foliolate and petiolate when mature or on older twigs; leaves of younger twigs often 1~2 foliolate and subsessile; young leaves often sericeous above and below but sometimes glabrous; leaflets apetiollate, elliptic to obovate, usually acute, sometimes emarginate, 4~16mm long; terminal leaflet > lateral leaflets. Flowers usually solitary, rarely paired, axillary; pedicels 5~13mm long. Calyx glabrous, bilabiate, about quarter the length of corolla; upper and lower lips entire or shallowly toothed. Corolla usually golden yellow, rarely partly red or tinged mauve, 16~25mm long. Pod black, oblong, many seeded, 15~60mm long with hairy margins; seeds brown or greenish-brown, ellipsoid, compressed, about 3mm long. (- Webb et. al., 1988)
An erect shrub up to c. 2-4m tall, with green, switch-like stems longitudinally ridged and angled (Wilson & Galloway 1993). The shrub is much-branched (Porteus 1993). Leaves are sparse mostly narrow and simple. The flowers are generally bright yellow and 2.5cm in length The pod is black when ripe and produces and explodes loudly on warm days, scattering the seed. The plant is perennial and has a stout taproot.
September, Ocrtober, November, December
Main Flower Colour
Other Flower Colour
Red / Pink
December-January, later in cooler areas (Timmins & MacKenzie 1995).
Reason For Introduction
Life Cycle Comments
Perennial. Seeds germinate readily, under a variety of conditions, in both autumn and spring. Seedlings develop slowly during the first year and plants do not flower until at least 2 years old. Plants are thought to live for 10-15 years. Plants found that were >20 years old (Hayes, 1998). The deeper the seed is buried the longer it appears to survive (Hayes, 1997). After 13 years about 2/3 of seed buried 15cm was intact but only 1/3 of seed buried at 3cm. Nearly all the seed remaining after 13 years was viable (Research by H. Harman and P. Syrett in Hayes, 1997).
Seeds prolifically. The pod produces 9 seeds/pod and usually in excess of 2 000 pods/bush and forms a substantial seed bank. Seeds persist in seed bank (Atkinson 1997).
Seed is dispersed by the plants explosive pod (Timmins & MacKenzie 1995) on hot days. The seeds can be spread by gravel, mud, animals, agricultural produce, machinery, people, tracks and railroads, roads and water. Small plants (0.5 m, 2 years old) flung seeds up to 1.5m away (Hayes, 1997)
The plant is tolerant to drought and shade and highly tolerant to frost. The plant is intolerant to poor drainage. Physical damage to the plant results in resprouting, if not severe, although fire will kill plants. Heavy grazing will kill the plant, resprouting will occur after light grazing. Seedlings tolerate a wide range of soil conditions. Young plants can tolerate a wide range of light intensity and survive even in 90% shade. The plant is tolerant of dry, stoney conditions and has the ability to spread rapidly in the absence of grazing. Leaves are unpalatable. The plant tolerates a wide range of soil conditions.
The seeds of this broom species are poisonous. This is especially true if the seed are crushed or chewed before being swallowed.
This page last updated on 9 Dec 2010