Sycamore

(Also known as Oriental Plane tree)

Platanus orientalis

Family: Aceraceae

Type of weed:

Priority Weed Local Priority Weed. (See more weeds of the class.)

Flowering Months: , ,

Description

A deciduous tree with a spreading crown usually growing 12–25 m tall, but occasionally reaching 35 m. The trunks and branches of younger trees are a smooth grey bark, while the bark of older trees becomes scaly. Older trunks sometimes have a reddish-brown or orange-brown colour where the scaly bark flakes off. The younger branches and growing tips are smooth, hairless, green or reddish-green in colour.

The large leathery leaves are oppositely arranged along the stems. They are divided into 3–5 broad lobes which are cut about halfway to the base of the leaf and resemble the fingers of a hand. They are hairless and have coarsely toothed margins. The upper surfaces of the leaves are usually dark green and their undersides a lighter green, gradually changing colour as they age and eventually shed during autumn and winter.

The flowers are yellow-green and are produced in spring on a 10–20 cm stalk with 20–50 flowers on each stalk.

The distinctive green or reddish-green v-shaped, ‘helicopter’ fruit are borne in drooping clusters. The seeds are 5–10 mm long.

Dispersal

It spreads prolifically from wind-blown seed for large distances into bushland.

Impact on bushland

Sycamore can invade areas over large distances, forming dense stands of trees that create heavy shade, replacing native vegetation, making regeneration of native plants impossible.

Distribution

,

Alternative planting

Native plants

  • Black She Oak (Allocasuarina littoralis)
  • Blackwood Wattle (Acacia melanoxylon)
  • River Oak (Casuarina cunninghamiana)
  • Narrow Leaved Paperbark (Melaleuca linarifolia)

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

CONTROL MEASURE: THE PLANT SHOULD BE FULLY AND CONTINUOUSLY SUPPRESSED AND DESTROYED

Seedlings of Sycamore pull out easily. Older plants form a long tap-root that makes pulling out difficult.

Cut and paint saplings and small plants with herbicide. Cut the main stems off at ground level and immediately apply undiluted herbicide to the cut surface. Do not allow soil to cover the cut surface. If Sycamore is felled, cut the stems and branches and stacked in a dry place place off the ground (rafting), as they can take root if in contact with the ground.

Drill and inject larger plants with herbicide. This technique has the advantage of allowing the plant to die without the need to raft cut material. By the time it dies and decomposes there will be no risk of reshooting.

For more info

For key points on these techniques:

Local Priority Weed

Control measures:

  • The plant should be fully and continuously suppressed and destroyed.
  • Plants under 4 metres in height should be fully and continuously suppressed and destroyed.
  • The spread of this plant should be adequately contained to prevent spread impacting on priority assets. Weed notices will only be issued for these weeds under special circumstances.