Basic Information
Common Name: Boswellia dalzielii
Scientific Name: Boswellia dalzielii
Native Habitat: Dry woodlands, rocky hillsides, and savannas across the Sahel region of West Africa, including countries like Nigeria, Chad, Niger, Mali, Burkina Faso, Senegal, and Ghana. It thrives in arid or semi-arid conditions.
History / Discovery / Cultivator
The genus Boswellia holds a revered place in human history, primarily due to the aromatic resins, commonly known as frankincense, harvested from various species. While Boswellia sacra and Boswellia carterii are perhaps the most famous for their historical significance in religious ceremonies, perfumery, and traditional medicine across the Middle East and Northeast Africa, Boswellia dalzielii represents the genus’s presence and importance in the West African landscape.
The formal scientific description of Boswellia dalzielii is attributed to Scottish botanist Thomas Archibald Sprague, who published his findings in 1913. The species name ‘dalzielii’ honors Dr. John McEwan Dalziel, another Scottish botanist and medical doctor who spent significant time working in British West Africa (particularly in Nigeria and Ghana) and made extensive collections and studies of the region’s flora. Dalziel’s foundational work, “The Useful Plants of West Tropical Africa,” first published in 1937, remains a key reference, documenting the indigenous uses of plants, including Boswellia dalzielii.
Unlike its Arabian and Horn of Africa cousins whose resins dominated ancient trade routes, the resin of Boswellia dalzielii has historically been of more regional importance. Indigenous peoples in West Africa have long recognized its value. The tree’s wood is used for timber, carving, and firewood. Traditionally, the leaves, bark, and resin have found applications in local pharmacopoeias for treating various ailments, including fever, rheumatism, and respiratory issues. The bark is particularly noted in traditional medicine for its anti-inflammatory properties and its use in treating wounds and stomach complaints.
Boswellia dalzielii is a pachycaul tree, meaning it develops a swollen trunk or base adapted for water storage, a common trait among plants in arid environments. This characteristic, along with its adaptability to harsh, dry conditions, highlights its evolutionary success in the challenging Sahelian climate. While not as widely cultivated globally as some ornamental or fruit trees, Boswellia dalzielii is maintained in certain agricultural and traditional settings within its native range for its medicinal properties, wood, and resin. It is also gaining interest among succulent and caudiciform plant collectors internationally due to its unique form and resilience, though it remains less common in cultivation than many other dry-adapted species.
The geographical origins of Boswellia dalzielii are firmly rooted in the dry belt of West Africa. It is a species specifically evolved to tolerate the prolonged dry seasons and intense heat characteristic of the savanna and Sahelian zones. Its presence across multiple West African nations underscores its ecological significance in these ecosystems, often growing in rocky outcrops or areas unsuitable for conventional agriculture, thus utilizing marginal lands and contributing to biodiversity and local resource provision in arid environments. The tree’s survival strategies, such as shedding leaves during the harshest dry periods, allow it to persist where less adapted species cannot.
In recent times, there has been renewed scientific interest in the chemical composition and pharmacological potential of Boswellia dalzielii resin and bark extracts, aiming to validate and potentially modernize its traditional medicinal uses. This research may further elevate the profile of this distinct West African frankincense species on a global scale, building upon centuries of indigenous knowledge documented by figures like Dalziel and described scientifically by botanists like Sprague.
Plant Care Summary
| Category | General Requirement | Notes |
|---|---|---|
| Light | Full sun | Requires bright light to maintain compact growth and healthy caudex. Can tolerate some light shade but may become leggy. |
| Water | Low | Drought-tolerant. Water thoroughly only when soil is completely dry, especially during the growing season (warm months). Reduce significantly or cease watering during dormancy (cool/dry season). |
| Humidity | Low | Prefers low humidity typical of its native arid habitat. Good air circulation is beneficial. |
| Temp. Range | Warm (50°F+) | Thrives in warm conditions. Protect from cold; cannot tolerate frost. Ideal temperatures are 70-90°F (21-32°C) during growth. |
| Soil Type | Well-draining | Requires extremely well-draining soil. Use a succulent or cactus mix, or a mix of gritty materials like pumice, perlite, and sand with a small amount of organic matter. |
| Fertilizer | Minimal | Feed sparingly, perhaps once or twice during the peak growing season with a diluted balanced liquid fertilizer. Avoid over-fertilizing. |
| Toxicity | Low | Generally considered low toxicity. Resin may cause mild skin irritation in sensitive individuals. Ingestion unlikely to cause severe issues but avoid. |
Botanical Insights
Adaptations
Boswellia dalzielii exhibits remarkable adaptations enabling its survival in arid and semi-arid West African environments. Its most notable feature is its pachycaul (swollen) trunk and branches, which serve as significant water storage reservoirs, allowing the tree to endure prolonged dry periods. The thick bark provides protection against intense sun and potential fires. The species is deciduous, shedding its leaves during the dry season to conserve water when moisture is scarce, leafing out again when rains return. Its root system is likely adapted to either tap into deeper water sources or efficiently absorb sporadic rainfall from the upper soil layers. The production of fragrant resin is another adaptation, potentially deterring herbivores and sealing wounds to prevent desiccation or infection.
Propagation Methods
Propagation of Boswellia dalzielii is typically done by seed or cuttings, though both methods can present challenges. Seeds should ideally be fresh for optimal germination rates; however, seeds can be slow and germination can be erratic. Cuttings can be taken from firm, woody stems. They require callusing for several days to weeks before being placed in a very gritty, well-draining substrate. Rooting success from cuttings can be low and slow, often requiring heat and careful moisture management to prevent rot. Grafting onto more vigorous rootstock is sometimes employed to speed growth.
Toxicology
Boswellia dalzielii, like most members of the Burseraceae family (which includes frankincense and myrrh species), is generally considered to have low toxicity. The resin, while aromatic and used in traditional medicine, may cause mild skin irritation in individuals with sensitivity, especially upon prolonged contact. Ingesting plant parts is not common, and while there are no widely reported cases of severe poisoning from Boswellia dalzielii, large quantities of plant material could potentially cause mild digestive upset. The plant is not listed among major toxic plants for common household pets like cats and dogs by veterinary organizations. However, it is always prudent to prevent pets from ingesting any unfamiliar plant material.
Common Problems
Pests:
- Scale insects (often found on stems and branches)
- Mealybugs (especially in crevices and leaf axils)
- Spider mites (less common but can occur in dry, low-airflow conditions)
Diseases:
- Root rot (the most significant risk, caused by overwatering or poor drainage)
- Fungal leaf spots (less common in dry conditions but possible in high humidity or with excessive watering)
Other:
- Leaf drop (natural dormancy response to dry conditions or cold temperatures; also a sign of stress from improper watering – too much or too little)
- Wrinkled or shriveled caudex/trunk (indicates severe underwatering or root issues preventing water uptake)
- Lack of growth (often due to insufficient light, cold temperatures, or dormancy)
Rarity & Value
Rarity:
Boswellia dalzielii is not widely cultivated outside of its native range and botanical collections, contributing to its rarity in the horticultural trade compared to more common ornamental plants. Factors contributing to its limited availability include: propagation difficulties (especially from cuttings), slow growth rate, and the specialized care requirements needed to mimic its arid native habitat, which deters many growers. It is also not typically grown on a large scale for resin production for the international frankincense market, focusing production on local needs or specific regional uses.
Value:
The market value of a Boswellia dalzielii specimen is influenced by several factors. Size and age are significant; larger, older specimens with well-developed, attractive pachycaul trunks command higher prices due to their slow growth. The form and character of the caudex are also important to collectors of caudiciform plants. The health and condition of the plant, including the absence of pests or diseases and evidence of robust growth, contribute to its value. Provenance (where the plant was grown) and its availability from specialist nurseries also play a role. As a less common Boswellia species in cultivation, it appeals to collectors seeking unusual and architecturally interesting arid-adapted plants.
