Ajo
Caryocar costaricense
Native Region
Costa Rica to Venezuela
Max Height
35-50 meters (115-165 feet)
Family
Caryocaraceae
Conservation
EN
Uses
Distribution in Costa Rica
Legend
Elevation
0-800m
Regions
- Limón
- Puntarenas
Season
Flowering
Feb-Apr
Fruiting
Jul-Sep
Ajo (Costa Rican Souari)
The Ajo (Caryocar costaricense), also called Ajillo or Costa Rican Souari, is one of the largest and most impressive trees in Costa Rica's lowland rainforests. Rising above the canopy on massive buttressed trunks, these emergent giants can reach 50 meters tall. Listed as Endangered by the IUCN and protected under CITES Appendix II, the Ajo faces ongoing threats from habitat loss and deforestation.
Quick Reference
- Scientific Name
- Caryocar costaricense
- Family
- Caryocaraceae (Souari Family)
- Max Height
- 35-50 m (115-165 ft)
- Conservation
- Endangered (IUCN)
- CITES
- Appendix II
- Habitat
- Lowland rainforest
iNaturalist Observations
Community-powered species data
50
Observations
186
Observers
Why This Tree Matters
Cathedral of the Rainforest
The Ajo is what ecologists call an "emergent"—a tree that rises above the main forest canopy, standing alone against the sky like a living cathedral spire. These towering giants play crucial roles in rainforest ecosystems:
Ecological Importance
- Habitat: Crown provides nesting for raptors and other birds
- Food source: Nutritious seeds feed agoutis, peccaries, and other wildlife
- Forest structure: Creates vertical habitat diversity
- Carbon storage: Massive biomass stores significant carbon
- Microclimate: Influences temperature and humidity below
Cultural Significance
- Traditional food: Edible nuts harvested by indigenous peoples
- Medicinal use: Traditional remedies from various parts
- Landmark: Often used as reference points in forests
- Spiritual: Revered as sacred trees in some communities
📸 Photo Gallery
Photos sourced from iNaturalist's community science database. Browse all observations →↗
Taxonomy & Classification
The Caryocaraceae is a small family of just 2 genera and about 25 species, found in tropical Central and South America. They are known for their hard-shelled fruits containing edible seeds. The most famous relative is the Pequi (Caryocar brasiliense) of Brazil, whose spiny pulp is a culinary delicacy.
Common Names
| Language | Common Name(s) | Notes |
|---|---|---|
| Spanish | Ajo, Ajillo | Garlic-like scent of inner bark |
| English | Costa Rican Souari | Scientific/conservation name |
| Spanish (local) | Almendro de montaña | Mountain almond |
| Trade | Souari Nut Tree | International trade name |
The name "Ajo" (garlic) comes from the garlicky odor of the inner bark when cut.
Physical Description
Overall Form
The Ajo is a massive, towering tree that dominates the forest skyline. Its thick, buttressed trunk supports a spreading crown that emerges above surrounding trees.
Distinctive Features
Trunk & Roots
- Buttresses: Massive, plank-like buttresses extending 3-6 m
- Bark: Gray-brown, rough, sometimes scaling
- Inner bark: Garlic-scented when cut
- Wood: Moderately hard, resistant
Leaves & Flowers
- Leaves: Trifoliate (3 leaflets), opposite
- Leaflets: Large, leathery, 10-25 cm long
- Flowers: White to cream, in terminal clusters
- Petals: Numerous, brush-like stamens
- Fragrance: Sweet, attracting nocturnal pollinators
Fruit & Seeds
The Ajo produces large, rounded fruits containing 1-4 kidney-shaped seeds:
- Fruit size: 8-12 cm diameter
- Fruit weight: Up to 500 grams
- Seed structure: Hard shell with oily kernel
- Edibility: Nutritious, eaten by wildlife and humans
- Oil content: Seeds are 60-70% oil
The seeds were traditionally an important food source for indigenous peoples.
Habitat & Distribution
Geographic Range
The Ajo is found from Costa Rica through Panama to Colombia and Venezuela, always in lowland wet forests.
| Region | Presence | Status |
|---|---|---|
| Osa Peninsula | Present | Key population |
| Caribbean lowlands | Present | Fragmented |
| Atlantic slope | Present | Protected areas |
| Panama | Present | Throughout lowlands |
| Colombia/Venezuela | Present | Eastern populations |
Preferred Habitat
- Forest type: Primary lowland wet forest
- Canopy position: Emergent (above canopy)
- Elevation: Sea level to 800m
- Rainfall: High (3,000-5,000 mm/year)
- Soil: Well-drained, often alluvial
Conservation Status
IUCN Assessment
Endangered
IUCN Red List Status
CITES Listing
Caryocar costaricense is listed on CITES Appendix II, meaning international trade is regulated to prevent exploitation that would threaten the species. Export permits are required for any timber or products.
Threats
| Threat | Severity | Notes |
|---|---|---|
| Deforestation | Critical | Primary lowland forest rapidly disappearing |
| Agricultural conversion | High | Cattle ranching, palm oil plantations |
| Logging | Moderate | Valuable timber historically exploited |
| Slow regeneration | Moderate | Large seeds, slow growth rate |
| Climate change | Uncertain | Lowland species may face temperature stress |
Conservation in Costa Rica
Where Ajo trees are protected:
- Corcovado National Park: Prime Osa Peninsula habitat
- Tortuguero National Park: Caribbean lowland forests
- Braulio Carrillo National Park: Atlantic slope
- La Selva Biological Station: Research and protection
- Private reserves: Various conservation lands
Traditional Uses
Food & Nutrition
Edible Seeds
The Ajo's seeds are nutritious and were traditionally harvested:
- Protein: ~15% of dry weight
- Fat: 60-70% (primarily oleic acid)
- Preparation: Roasted, boiled, or pressed for oil
- Taste: Mild, nutty flavor
- Caution: Raw seeds may cause digestive upset
Oil Extraction
The high oil content made these seeds valuable:
- Oil quality: Similar to olive oil
- Uses: Cooking, lighting, cosmetics
- Extraction: Traditional pressing methods
- Modern potential: Interest in sustainable harvest
Medicinal Uses
Traditional medicine employed various parts:
- Inner bark: Treatments for parasites
- Seed oil: Skin conditions, wounds
- Leaves: Fever remedies
- Root bark: Various traditional preparations
Traditional uses should be understood in cultural context. Always consult healthcare professionals for medical concerns.
Ecological Relationships
Wildlife Dependencies
| Animal | Relationship | Importance |
|---|---|---|
| Agoutis | Seed disperser/predator | Critical for regeneration |
| Peccaries | Seed consumer | Forest floor foragers |
| Parrots | Seed consumer | May disperse some seeds |
| Harpy Eagles | Nesting habitat | Use emergent crowns |
| Bats | Pollinator | Nocturnal flower visitors |
The Ajo's large, heavy seeds depend on large mammals like agoutis and peccaries for dispersal. As these animals decline due to hunting and habitat loss, the tree's ability to regenerate is compromised—a classic example of how species extinctions cascade through ecosystems.
Identification Guide
How to Identify Ajo
Definitive Characteristics:
- Massive buttressed trunk extending 3-6 m
- Emergent crown rising above canopy
- Trifoliate leaves (3 leaflets)
- Large round fruits on ground below
- Garlic scent when bark is cut
Where to See Ajo in Costa Rica
| Location | Access | Notes |
|---|---|---|
| Corcovado National Park | Guided access | Best remaining populations |
| Tortuguero National Park | Boat/guided | Caribbean lowland forests |
| La Selva Biological Station | Research visits | Labeled specimens |
| Osa Peninsula reserves | Various access | Private conservation lands |
External Resources
Official conservation assessment
Trade regulation information
Community observations
References
📚 Scientific References & Further Reading
Prance, G.T. & Silva, M.F. (1973). Monograph of Caryocaraceae. Flora Neotropica
IUCN (1998). Caryocar costaricense. The IUCN Red List of Threatened Species
Cordero, J. & Boshier, D.H. (2003). Árboles de Centroamérica. OFI/CATIE
The Ajo represents the majesty of Costa Rica's lowland rainforests—trees so large they create their own ecosystems, supporting countless species from their buttressed roots to their sky-high crowns. As these forests disappear, so too do these giants. Protecting primary rainforest isn't just about saving individual species—it's about preserving the architectural complexity that makes tropical forests the most biodiverse ecosystems on Earth.
