Quick Facts

Quick facts

• Madeira Broom (Genista stenopetala) is a spreading shrub that is originally from the Canary Islands.
• Madeira Broom is currently known from populations in South Australia, Victoria, New South Wales and Tasmania.
• It is both an environmental weed, and also a weed of waste places, urban areas and degraded roadsides. There are no reports of impacts on agriculture and livestock.
• If not eradicated it has the potential to spread further and invade additional areas of native vegetation.
• Identification can sometimes be difficult due to confusion with G. x spachiana, and possible hybrids or intermediates between white Spanish Broom (G. monspessulana) and Madeira Broom.

What Does It Look Like?

What is it?

Madeira Broom (Genista stenopetala) is an upright or spreading shrub or small tree to 4 m high. The twigs are rounded in cross-section, and ribbed. The compound leaves have a stalk 4–25 mm long and each leaf has 3 leaflets. The leaflets are narrowly oval or egg-shaped with the widest part above the middle, 5–40 mm long and 3–12 mm wide. The central leaflet is longer than the two side leaflets. The leaflets are sparsely hairy, often with scattered hairs on the upper surface.

The yellow pea flowers are arranged in groups of about 10–30 at the end of the leaf-bearing stems.

The fruit (pod) is narrow-oblong (2–4 times longer than broad, with nearly parallel sides), 20-40 mm long, flattened, densely silky-hairy, and opens to release the seeds when ripe. There are 5–7 black seeds in each pod (Webb et al. 1988; McClintock 1993; Harden 2002; PlantNet 2007).

For further information and assistance with identification of Madeira Broom contact the herbarium in your state or territory.

Flower colour

Yellow

Growth form (weed type/habit)

Tree, Shrub

Where it currently grows? Preferred habitat

In the Canary Islands where it is native, Madeira Broom is frequent in and below the laurel forest zone and Erica heath regions, from 600 to 1500 m above sea level (Bramwell & Bramwell 1974).

In Australia it is found in regions with a warm temperate climate, and moderate rainfall. It has been recorded from degraded roadsides, railway embankments, waste places, and as an environmental weed in native woodlands and tall open forest (Webb et al. 1988; McClintock 1993; eFlora SA 2001; Coveny 2007, pers. comm.; National Herbarium of Victoria 2007; Stajsic 2007, pers. comm.;).

Are there similar species?

The complex horticultural history and breeding that has occurred in this group make identification very difficult.

There is confusion with G. x spachiana (a garden hybrid, probably between G. canariensis and G. stenopetala). There also appear to be intermediates or hybrids between Cape Broom (G. monspessulana) and Madeira Broom (Spencer 2002; Stajsic 2007, pers comm.). G. x spachiana is barely distinguishable from Madeira Broom and some consider them to be the same taxon (GRIN 2007; Hosking 2007, pers.comm.). Both were listed in Ross & Walsh (2003) to raise awareness among collectors that there is more than one entity, in the hope that additional specimens will be lodged at herbaria and may aid in resolving some of the confusion (Stajsic 2007, pers. comm.).

Cape Broom (Genista monspessulana) differs from Madeira Broom in having fewer flowers (3 to 9) per cluster and the flowering axis shorter than 10 mm. Madeira Broom has a longer flowering axis (10 to 130 mm long) and 10 to 40 flowers per cluster (Webb et al. 1988; Stajsic 2007, pers. comm.).

Flax-leaf Broom (G. linifolia) differs from Madeira Broom in having almost stalkless or very shortly stalked leaves and leaflets which are narrow and more or less straight-sided. This contrasts with the stalked leaves of Madeira Broom which are oval or reversely egg-shaped (Webb et al. 1988; Jeanes 1996).

A small infestation of Genista depressa [as Genista tinctoria subsp. depressa] has been recorded at Buckleys Falls, near Geelong, although it apparently has been eliminated (National Herbarium of Victoria 2007). It differs from Madeira Broom in having leaves consisting of a single leaflet (Jeanes 1996).

Why Is It A Weed?

What are its impacts?

Native ecosystems: A number of Genista species are highly invasive. They can invade a variety of native ecosystems such as grasslands, woodlands, heathlands, forests, riparian areas and near coastal vegetation, such as on the Mornington Peninsula in Victoria, as well as disturbed and degraded areas generally and roadsides (Muyt 2001; Stajsic 2007, pers. comm.). Being legumes, Genista species fix nitrogen, and may have the potential to increase soil fertility, encouraging other weeds to invade. Dense infestations of the related species Cape Broom and Flax-leaf Broom shade out native ground-flora and smaller shrubs, and eventually come to dominate the shrub layer (Muyt 2001).

Agriculture: There are currently no reports of Madeira Broom impacting agriculture in Australia. (Stajsic 2007, pers. comm.).

How does it spread?

Madeira Broom is spread solely by seeds, which are ejected explosively as the pods dry out on warm, sunny days during summer. Most of the seeds probably fall within a few metres of the parent plant. They may be further dispersed by water if near streams, mud on machinery (such as road graders, slashers), vehicles and footwear. Birds, ants and stock as well as dumped seed-bearing garden refuse are other means of dispersal for Genista species in general (Parsons & Cuthbertson 1992; Muyt 2001).

What is its history in Australia?

Madeira Broom was originally introduced into Australia as an ornamental garden plant, and it remains commercially available in some nurseries in Australia. The earliest specimens held in the state herbaria date from the late 1940s to through to the early 1960s. It is unknown at what time Madeira Broom became naturalised (eFlora SA 2001; Buchanan 2007, pers. comm.; Coveny 2007, pers. comm.; National Herbarium of Victoria 2007).

How To Manage It?

Best practice management

There is relatively little information about the control of Madeira Broom.

Given that Genista is related to the genus Cytisus, the control methods applied for English Broom (Cytisus scoparius) and White Spanish Broom (C. multflorus) can be used to control or eradicate Madeira Broom (Muyt 2001).

Because of the longevity of the soil-stored seeds of Genista species, which can remain dormant for at least ten years eliminating larger incursions has to be considered a long-term endeavour (Muyt 2001).

Non-chemical control: Seeds of Genista species usually fail to establish in dense shade. As such creating any soil disturbance will normally induce the mass germination of soil stored seeds, which may continue to germinate for a number of years. In established infestations of Genista, seed numbers can reach several thousand per square metre (Muyt 2001).

Mechanical control: Bulldozing and then burning has been used for larger infestations of English Broom Cytisus scoparius (Parsons & Cuthbertson 1992). However, to date there are no extensive populations of Madeira Broom requiring this approach. The advantages of bulldozing and burning are that the adult plants are killed, and the seeds are stimulated to germinate, thus quickening the process of waiting for seeds to germinate so they can be destroyed (Cochrane 2001).

Manual control: Hand weeding or hoeing is an option for where there are only isolated plants. 

Chemical control: Follow-up chemical management, such as spraying the seedlings with herbicide is necessary and may need to be done for many years (CRC 2003). In smaller incursions the cut and paint method can be applied (Muyt 2001).

Please see the Australian Pesticides and Veterinary Medicines Authority for chemical information http://www.apvma.gov.au .

Madeira Broom has also been recognised as a target for biological control through a cross-jurisdictional government process. This allows activities to be undertaken to develop effective biological controls.

Does it have a biological control agent?

YES

When does it grow? (lifecycle/growth calendar)

Madeira Broom normally flowers between July and April (Webb et al. 1988).

There is little information available about the life cycle of Madeira Broom. Most of the growing period of other Genista species in southeastern Australia occurs during the warmer months (National Herbarium of Victoria 2007; Stajsic 2007, pers. comm.). Cape Broom (Genista monspessulana) and Flax-leaf Broom (G. linifolia) do not produce flowers until they are at least two years old, and usually live no more than ten years (Parsons & Cuthbertson 1992; Muyt 2001).

Where Is It Found?

Which states and territories is it found?

NSW, SA, TAS, VIC

What areas within states and territories is it found?

The populations of Madeira Broom in Australia are small, or only consist of scattered plants. All of the known incursions in Victoria vary from one to several plants (Stajsic 2007, pers. comm.). It is recorded in western Victoria, in Ballarat and in several Melbourne suburbs.

In South Australia it has become naturalised in the Southern Lofty Ranges and near Mt Gambier

Madeira Broom is abundantly naturalised in Epping in Sydney, New South Wales (Coveny 2007, pers. comm.; Herbarium of Victoria 2007)

It is naturalised in Tasmania from the margins of Hobart (particularly the slopes of Mt Wellington) and the Tasman Peninsula (eFlora 2001; Buchanan 2007, pers. comm.; Stajsic 2007, pers. comm.).

Where does it originate?

Madeira Broom is native to the Canary Islands (GRIN 2007).

National And State Weed Listings

Is it a Weed of National Significance (WONS)?

NO

Where is it a declared weed?

ACT, WA

Government weed strategies and lists – Weeds Australia

Is it on the National Alert List for Environmental Weeds?

NO

Government weed strategies and lists – Weeds Australia

Is it on the Agricultural Sleeper List?

NO

Government weed strategies and lists – Weeds Australia

Names And Taxonomy

Main scientific name

Genista stenopetala

Other scientific names (synonyms)?

• Teline stenopetala Webb & Berthel.
• Genista maderensis (Webb & Berthel.) Lowe (misapplied by Weber, J.Z. 1986, Papilionoideae. Flora of South Australia Edn 4. 2: 406.; Beadle, N.C.W., Evans, O.D. & Carolin, R.C. 1962, Handbook of the Vascular Plants of the Sydney District and Blue Mountains. 255.; Curtis, W.M. & Morris, D.I. 1975, Angiospermae: Ranunculaceae to Myrtaceae. The Student's Flora of Tasmania Edn 2. 1: 152.)

Does it have other known common name(s)?

Sweet Broom, Easter Broom