Sterculia urens is the karaya gum tree, kulu in Hindi: a pale, ghostly tree of dry rocky hills whose bark is tapped for gum karaya. The gum is used worldwide as a thickener, a bulk laxative and a dental adhesive, and India is the main producer. Tapping provides cash for forest communities, but heavy tapping kills trees.
- Botanical name
- Sterculia urens Roxb.
- Family
- Malvaceae
- Tamil
- Kitholi
- Hindi
- Kulu
- Parts used
- Gum (industrial)
- Habit
- Gum Sterculia; gum-ghatti is Terminalia
- Last updated
- 2026-10-25
How to recognise Karaya
The bark is smooth, white to pinkish-grey and peels in papery flakes, so leafless trees stand out like ghosts on rocky hillsides in the dry season.
The leaves are large, palmately lobed and clustered at the branch tips. Small yellowish flowers come in sprays while the tree is bare.
The fruit is a cluster of red, star-arranged pods covered in stinging bristles. That is what urens, “burning”, refers to.
Gum ghatti comes from a different tree, Terminalia anogeissiana.
Traditional use of Karaya
Gum trade
Tappers cut or blaze the bark and collect the hardened gum, which is sold through forest cooperatives in states such as Andhra Pradesh, Telangana, Madhya Pradesh and Gujarat.
Indian forest economy
Modern notes on Karaya
Gum karaya (food additive E416) swells in water. It is used in food as a thickener and stabiliser, in medicine as a bulk laxative, and in denture adhesives and ostomy seals.
Studies on tapping found that intense blazing reduces tree survival, which led to guidelines on tapping depth and frequency.
Karaya safety
As a bulk laxative it must be taken with plenty of water, or it can cause blockage. Do not handle the fruit bristles.
Ecology and sourcing
It grows on dry, rocky hills and in deciduous forest across central and peninsular India.
Its range has shrunk as old trees died from over-tapping. Regeneration is slow on poor soils.
Related plants
Also in Malvaceae
Questions about Karaya
Is Karaya gum ghatti?
No. Gum ghatti comes from Terminalia anogeissiana.
What is gum karaya used for?
As a food thickener, a bulk laxative and a dental adhesive.
Why does the fruit sting?
Its pods are covered in irritating bristles.
Sources
- Sterculia urens Roxb. — Plants of the World Online, Kew (search) (accessed 2026)
- Wikidata item Q3498736 (Sterculia urens)
Educational page about a plant. It is not medical advice, not a diagnosis, and not an offer to sell. Traditional use is historical. If you need care, ask a licensed clinician. Questions: hello@meevamed.com.