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  4. Castor oil plant
What Are Weeds?

Weed Information Sheet

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Castor oil plant

Botanical Name

Ricinus communis

Family

Euphorbiaceae (spurge)

Also known as

Castor bean plant

Where is it originally from?

Africa and Eurasia

What does it look like?

Smelly, clump forming shrub (<2+ m) with glossy long-stalked, five-finger-like leaves (15-45 cm long) that start off dark reddish purple or bronze and gradually changing to a dark green, sometimes with a reddish tinge, as they mature. Spikes of green or reddish flowers develop into spiny greenish (to reddish-purple) capsules which split to release large, oval, shiny, bean-like seeds that are very poisonous.

Why is it weedy?

Grows vigorously in disturbed areas and spreads easily and quickly.

How does it spread?

Capsules split open to eject seeds explosively.

What damage does it do?

Out-compete native species for resources.

Which habitats is it likely to invade?

Disturbed sites.

What can I do to get rid of it?

1. Cut down stems and leave to rot down. Dig out roots. Remove seeds for disposal to landfill.
Due to the risk that castor oil plant poses to human and animal health, caution should be taken when attempting any control and removal of this weed. Wear protective clothing, gloves and eye protection before starting control work.

What can I do to stop it coming back?

Check controlled sites regularly for any new seedlings.

Images

Photo: Trevor James
Photo: Trevor James
Photo: Trevor James
Photo: Trevor James
Photo: Trevor James
Photo: Trevor James
Photo: Trevor James
Photo: Trevor James
Photo: Trevor James
Photo: Trevor James

Download PDF Information Sheet

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  • Home
  • Weedbusters
    • Who are Weedbusters?
  • What Are Weeds?
    • Weed List
    • Controlling Weeds
      • Controlling Pest Shrubs & Trees
      • Controlling Pest Vines
      • Controlling Pest Herbs & Ground Covers
      • Controlling Pest Grasses
      • Controlling Pest Aquatic Weeds
    • Disposing of Weed Waste
    • Banned Plants
  • Get Involved
    • Become a Weedbuster
    • Weedbusters Near You
    • Weed Quiz
  • Resources
    • How to…
      • Raise Weeds Awareness
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    • Weedbusting Guide
    • Plant Me Instead Booklet
    • Using Weedbuster photographs
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