The Pili tree (Canarium ovatum) is a tropical tree native to the Philippines, cultivated for centuries for its edible nuts. These versatile nuts are recognized for their unique flavor and nutritional value. The Pili tree serves as a valuable food source and economic resource in its native regions.
Understanding the Pili Tree
The Pili tree is a tropical evergreen, reaching 20 to 25 meters tall, often developing a buttressed trunk up to 50 centimeters in diameter. Its leaves are spirally arranged, imparipinnate, and can grow up to 40 centimeters long, featuring dark green leaflets. The tree is predominantly dioecious, with male and female flowers typically on separate trees.
The fruit is a drupe, 4 to 7 centimeters long and 2.3 to 3.8 centimeters in diameter. It has a thin exocarp that ripens from light green to purplish-black, encasing a fibrous mesocarp and a hard shell protecting a single kernel. Pili trees thrive in tropical rainforests, particularly in the Philippines’ Bicol region, benefiting from warm temperatures and 2,000 to 3,000 mm of annual rainfall. They demonstrate resilience, resisting strong winds and typhoons.
Growing and Caring for Pili Trees
Pili trees are adaptable to various tropical growing conditions, but specific care practices optimize their health and productivity. Proper site selection, consistent watering, appropriate fertilization, and strategic pruning are important for successful cultivation and a bountiful harvest of nuts.
Site Selection and Planting
Pili trees grow best in deep, fertile, well-drained soils, though they tolerate a wide range of soil types, including clay, volcanic, loamy, and silty soils. They require full sun exposure and cannot tolerate shade. Space trees 12 to 15 meters (40 to 50 feet) apart for mature canopy spread.
Propagation by budding or grafting is preferred for consistent quality and earlier fruiting, typically within 3 to 4 years compared to 5 to 6 years for seedling trees. Plant young seedlings when they are about 25-30 cm tall, ensuring their roots are carefully handled during transplanting.
Watering and Fertilization
Pili trees prefer climates with well-distributed rainfall, ideally 2,000 to 3,000 mm annually. While mature trees are drought-tolerant, young plants and trees during dry seasons benefit from regular watering. Avoid waterlogging, as well-drained soil is important for root health.
Fertilization begins after three years. A balanced NPK (Nitrogen, Phosphorus, Potassium) fertilizer, such as 14-14-14, is suitable. Apply about 150 grams of nitrogen fertilizer per tree annually, starting from the fourth year. Spread fertilizers evenly across the soil surface, extending from about 15 cm (6 inches) from the trunk out to the drip line.
Pruning and Maintenance
Pruning is beneficial for Pili trees, especially those from seeds or grafts, to encourage a strong structural framework in their early years. Removing dead, diseased, or crossing branches helps maintain tree health, air circulation, light penetration, and facilitates harvesting.
Pili trees are generally robust against serious pests or diseases, possibly due to their natural resin content. Anthracnose may affect young seedlings but is typically controllable with fungicides. Termites can sometimes attack the roots of older trees.
Harvesting Pili Nuts and Their Uses
Pili nuts are harvested when the fruit’s skin changes from green to purplish-black, typically about 10 months after pollination. Harvesting is often labor-intensive, involving climbing trees or gathering fallen fruits. A mature Pili tree yields 100 to 150 kilograms of unshelled nuts per season, with full production usually beginning around 12 to 15 years of age.
Pili nuts are primarily culinary. The kernel can be eaten raw, roasted, or candied, and used in confections like cakes, puddings, chocolates, or nut butters. The ripe fruit’s pulp is also edible after boiling. Beyond the kernel, the Pili tree offers other valuable products: its resin, Manila elemi, is used in perfumes, varnishes, and medicinal ointments. The wood is suitable for light construction and furniture, and the hard shells can be used as fuel or crafted into ornaments.
Nutritional Benefits of Pili Nuts
Pili nuts are recognized for their rich nutritional profile. They are notably high in healthy fats, primarily monounsaturated fats like oleic and linoleic acids, beneficial for heart health and lowering LDL cholesterol. A 30-gram serving contains about 22.5 to 24 grams of fat.
Pili nuts also provide a complete protein source, containing all essential amino acids. They are packed with various vitamins and minerals, including Vitamin E, an antioxidant that protects cells from damage. They are rich in magnesium, crucial for muscle and nerve function, energy production, and bone health, with a 30-gram serving supplying approximately 85 mg (19% of the daily value). Other minerals present are manganese, phosphorus, copper, zinc, calcium, and iron.