(Also known as English Broom)
Cytisus scoparius
Family: Fabaceae
Type of weed: Woody weed
Flower colour(s): Yellow
Priority Weed State Priority Weed. (See more weeds of the State Priority Weed class.)
Flowering Months: September, October, November
Description
Erect, woody perennial shrub to 3 m, with ridged, much-branched stems, common in disturbed areas.
Sparse, tiny grey-green leaves with three leaflets; older plants may be almost leafless.
Large numbers of bright yellow pea flowers, either single or in pairs, along the stems in spring.
Flat, green seed pods turn black, producing huge numbers of hard brown shiny seeds, believed to survive seventy years or more in the soil.
Don’t confuse with…
Large plants can be confused with native pea plants such as Gompholobium, because of a similar flower.
Small plants of Broom spurge (Ampera xiphoclada) can be confused with this weed because both have angular stems. Broom spurge is three-sided; broom is four-sided, or square, in cross section. The leaves and habit of Gonocarpus teucrioides, when less than 0.5 m tall, can also look similar.
Dispersal
Seed pods eject seeds up to 4 m from the plant (up to 6,000 per plant per year). Seeds can also be spread by water, animals, mud on shoes or tyres, or in contaminated soil. The plant germinates readily after a fire or soil disturbance.
Impact on bushland
Broom is extremely competitive with native plants, retarding the growth of many understory species, leading to a loss of biodiversity.
Broom alters the bushland habitat in which it grows — shading out native plants, keeping soil cool and changing soil chemistry — producing conditions that are unsuitable for local native plants.
Distribution
Lower Blue Mountains, Upper Blue Mountains
Alternative planting
Native plants
- Mountain Devil (Lambertia formosa)
- Hakea teretifolia
- Banksia spinulosa
- Native Dogwood (Jacksonia scoparia) (Lower Mountains)
- Sunshine Wattle (Acacia terminalis)
- Golden Glory Pea (Gompholobium latifolium)
- Native Pea Flowers (Pultenaea spp)
Council provides a tool, on its Mountain Landscapes website, to help you choose native alternative plantings. Choose your village, soil, vegetation community and the purpose of your planting, and the tool will give you suggestions.
There are native nurseries in several Blue Mountains villages, including Glenbrook, Lawson and Katoomba. Please also ask at your favourite local nursery.
Control
- Hand remove
- Spray
- Stem inject or frill
- Cut and paint
Manual control
Hand remove
Grasp stem at ground level. Rock weed backwards and forwards to loosen roots, then pull out gently. Carefully tap the roots to dislodge attached soil. Replace disturbed soil and pat down.
Considerations
- Leave weeds so that roots do not make contact with soil; on a rock, for instance. A small amount of debris may be hung in a tree or removed from the site.
- Vary the position of your body to avoid fatigue when removing plants by hand over extended periods.
Chemical control
Note: Herbicides that may be used for this weed include Glyphosate.
Spraying
Please consult the Herbicide page of this website to help you decide whether to spray, how to do it safely and more.
Stem injection or frilling
Stem injection
At the base of the tree, drill holes at a 45° angle into the sapwood (just under the outer bark) at two finger space intervals around the entire base of the tree. Repeat this process below the lowest branch
Frilling
As an alternative to drilling, make cuts into the sapwood with a chisel or axe. Fill each cut/hole with herbicide immediately. Repeat the process at 3 cm intervals around the tree.
Considerations
Plants should be healthy and actively growing. Deciduous plants should be treated in spring and autumn when leaves are fully formed. For multi-stemmed plants, inject or chip below the lowest branch or treat each stem individually. Herbicide must be injected immediately before the plant cells close (within 30 seconds before translocation of herbicide ceases.)
Cut and paint
Useful for small to medium sized woody weeds up to 10 cm in diameter.
Make a horizontal cut as close to the ground as possible with secateurs or loppers, and immediately apply concentrated Glyphosate to the exposed stump surface. Do not allow the surface to get covered with soil.
Specific control tips for this weed
- Hand pull seedlings.
- Cut and paint or stem inject large plants.
Follow-up is needed as removal of plants will stimulate the germination of seeds in the soil.
For key points on these techniques:
State Priority Weed
Control measures:
- The plant must be eradicated from the land and be kept fully and continuously suppressed and destroyed; and the land must be kept free of the plant.
- If the weed is part of a new infestation of the weed on the land, notify the local control authority as soon as practicable.
