Bas Cedar (Guazuma ulmifolia Lam.)

1) Botanical Identity and Description

• Scientific Name: Guazuma ulmifolia Lam.
• Family: Malvaceae (formerly placed in Sterculiaceae).
• Common Names: In Jamaica, it is most commonly known as Bas Cedar or Bass Cedar (a corruption of “Bastard Cedar”). Other regional names include Guácimo, Caulote, and Bastard Elm.
• Plant Description: Bas Cedar is a medium-sized, evergreen or semi-deciduous tree, typically growing 10-20 meters tall. Its bark is distinctive – dark brown, deeply fissured, and rough. The leaves are simple, alternate, and have a serrated margin, resembling those of an elm tree (hence the name ulmifolia, meaning “elm-leaved”). The flowers are small, pale yellow, and inconspicuous. The fruit is a hard, woody capsule that remains on the tree, containing numerous small seeds.
• Distribution: It is a pioneer species, native to tropical Americas and widely naturalised throughout the Caribbean, Central America, and South America. It is common in Jamaica, often found in pastures, disturbed areas, and secondary forests.

2) Traditional Uses in Jamaican and Caribbean Folk Medicine

Bas Cedar holds a significant place in the Jamaican “bush tea” tradition, primarily valued for its cleansing and protective properties.

• “Blood Purifier” and Detoxifier: This is one of its primary uses. The concept of “purifying the blood” in folk medicine often relates to clearing skin conditions, reducing inflammation, and promoting overall systemic cleansing. A decoction of the bark is consumed as a general cleansing tonic to “wash out” impurities from the body [1].
• Diabetes Management: It is a well-known folk remedy for diabetes, used to “cut sugar” or lower blood glucose levels. This use is prevalent not only in Jamaica but across Latin America [2].
• Respiratory Ailments: Due to its mucilaginous properties, a tea made from the leaves or bark is a traditional remedy for colds, flu, coughs, bronchitis, and sore throats. It acts as a demulcent, soothing irritated mucous membranes [3].
• Skin Conditions and Wound Healing: The bark and leaves are used both internally and externally for skin problems. A strong decoction is used as a wash or poultice for sores, rashes, ulcers, and infections to promote healing and prevent sepsis [4].
• Anti-inflammatory and Analgesic: The bark decoction is taken internally or used as a compress to relieve inflammatory conditions such as arthritis, rheumatism, and general muscle pain.
• Gastrointestinal Issues: In some traditions, it is used to treat diarrhoea, dysentery, and stomach aches due to its astringent (tannin) content.

3) Parts Used and Preparation Methods

• Primary Parts: The bark is the most valued and commonly used part, followed by the leaves.
• Secondary Parts: Roots and seeds are used less frequently, often incorporated into more complex “roots tonics” or “bush baths.”
• Preparation Methods:
  • Decoction (Bush Tea): The most common preparation. Strips of bark or a handful of leaves are boiled in water for 10-20 minutes. The resulting dark tea is consumed as is or sweetened with honey, typically one cup, one to two times daily.
  • Poultice: The bark or leaves are boiled, mashed, and applied directly to the skin for wounds or inflammation.
  • Wash/Soak: The cooled decoction is used to clean wounds or soothe skin rashes.
  • Tincture: In modern herbal practice, it may be prepared as an alcohol tincture, though this is less traditional in Jamaica.

4) Phytochemistry and Pharmacological Evidence

Scientific research has begun to validate many of the traditional uses of Guazuma ulmifolia, identifying key bioactive compounds.

• Key Phytochemicals:

  • Mucilaginous Polysaccharides: Responsible for the soothing, demulcent effect on the respiratory and digestive tracts [3].
  • Proanthocyanidins and Flavonoids (e.g., catechins): These compounds are potent antioxidants and are believed to contribute to the anti-diabetic and anti-inflammatory effects by protecting cells from oxidative damage [2, 5].
  • Tannins: Provide astringent properties, which help in wound healing and treating diarrhoea.
  • Saponins: Contribute to the antimicrobial and anti-inflammatory activity.

• Pharmacological Studies:

  • Antidiabetic Activity: Multiple animal studies have demonstrated the hypoglycemic (blood sugar-lowering) effects of G. ulmifolia leaf and bark extracts. The proposed mechanisms include inhibiting the absorption of glucose in the intestine and enhancing glucose uptake by cells [2, 6].
  • Anti-inflammatory and Analgesic: Extracts have shown significant anti-inflammatory activity in standard laboratory models (e.g., carrageenan-induced paw edema), supporting its use for pain and swelling [5].
  • Antimicrobial: Studies confirm its broad-spectrum antimicrobial activity against various bacteria and fungi, validating its traditional use for skin infections and wounds [4].
  • Antioxidant: The high flavonoid content gives the plant strong free-radical scavenging activity, which underpins its role as a “blood purifier” and general tonic [5].

5) Safety and Cautions

• General Safety: Bas Cedar is generally considered safe when consumed in traditional food and medicinal doses for short periods.
• Pregnancy and Lactation: Due to a lack of safety data, its use is not recommended during pregnancy or breastfeeding.

• Drug Interactions:

  • Diabetes Medications: Given its documented hypoglycemic effects, there is a potential risk of additive effects when combined with conventional anti-diabetic drugs (e.g., insulin, metformin), which could lead to hypoglycemia (dangerously low blood sugar). Close monitoring is essential [6].
  • Anticoagulants: Theoretically, its tannin and flavonoid content could interact with blood-thinning medications, though this is not well-documented.
• Long-Term Use: The safety of long-term, high-dose consumption has not been established.

6) Cultural Context and Significance

In Jamaica, Bas Cedar is a cornerstone of the bush medicine tradition, often grouped with other “cooling” and “cleansing” herbs. It is considered a reliable, everyday remedy rather than a powerful, spiritual “roots” tonic like Strong Back (Morinda royoc) or Medina (Eryngium foetidum). Its popularity stems from its wide availability and versatility.

The name “Bastard Cedar” effectively distinguishes it from the true, more aromatic Caribbean Cedar (Cedrela odorata), which is also used medicinally but for different purposes. This vernacular naming practice is common in Jamaican botany, reflecting a deep, practical knowledge of the local flora.

Key Takeaway

Bas Cedar (Guazuma ulmifolia) is a well-established medicinal tree in Jamaican and Caribbean folk medicine, revered primarily as a detoxifying “blood purifier,” a hypoglycemic agent for diabetes management, and a soothing remedy for respiratory and skin conditions. Modern scientific research provides strong support for its traditional uses, confirming its antioxidant, anti-inflammatory, antimicrobial, and anti-diabetic properties. While generally safe, caution is advised, particularly for individuals on diabetes medication.

References

[1] Lowe, H., Payne-Jackson, A., Beckstrom-Sternberg, S., & Duke, J. (2000). Jamaica’s Ethnomedicine: Its Potential in the Healthcare System. University of the West Indies.
[2] Alonso-Castro, A. J., et al. (2017). “Mexican Medicinal Plants Used for the Treatment of Diabetes: A Review.” Journal of Ethnopharmacology, 203, 1-20.
[3] Cáceres, A., et al. (1990). “Plants used in Guatemala for the treatment of respiratory diseases. 1. Screening of 68 plants against gram-positive bacteria.” Journal of Ethnopharmacology, 30(1), 55-73.
[4] Montero, J. F., et al. (2011). “Antimicrobial activity of Guazuma ulmifolia Lam. (Sterculiaceae).” Revista Boliviana de Química, 28(1), 1-5.
[5] Pérez, R. M., et al. (2005). “A review of the biological activity and chemical composition of the genus Guazuma.” Pharmaceutical Biology, 43(5), 405-414.
[6] Aguirre-Crespo, F., et al. (2006). “Hypoglycemic effect of Guazuma ulmifolia Lam. in normal and alloxan-diabetic mice.” Journal of Ethnopharmacology, 108(1), 1-5.

This article is copyrighted by Ital is Vital, 2025. Want to re-post this article? Visit our guidelines.

DISCLAIMER: THIS WEBSITE DOES NOT PROVIDE MEDICAL ADVICE
The information, including but not limited to, text, graphics, images and other material contained on this website are for informational purposes only. The purpose of this website is to promote broad consumer understanding and knowledge of various health topics. It is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider with any questions you may have regarding a medical condition or treatment and before undertaking a new health care regimen, and never disregard professional medical advice or delay in seeking it because of something you have read on this website.