Tītoki
Alectryon excelsus
The Tītoki (scientific name: Alectryon excelsus), also known as New Zealand oak, is a handsome and distinctive medium-sized evergreen tree endemic to New Zealand. A prominent member of the Sapindaceae family, it is celebrated for its glossy, dark olive-green foliage and its remarkable, scarlet-arilled fruit. Found throughout the North Island and the northern South Island, it is a characteristic component of lowland and coastal forests. Its rounded canopy and twisting trunk make it a significant architectural element of the native forest. Understanding this tree contributes to the appreciation of our rich biodiversity and heritage, and supports conservation efforts for all native species.
Plant Description
Identification and Physical Characteristics
Alectryon excelsus typically grows to 7-12 meters, though it can reach 20 meters in favorable conditions. It develops a spreading canopy and a distinctive twisting trunk with smooth, dark bark. The leaves are imparipinnate, glossy, and dark olive-green, with young branchlets and leaflets covered in fine, rusty-brown hairs. A key identifying feature is its unique fruit: a woody, rusty-haired capsule that splits open to reveal a single, shiny black seed partially encased in a brilliant red, fleshy aril. This striking contrast between the seed and aril is a hallmark of the species. Flowering occurs from spring to early summer, producing small, purplish fragrant flowers in panicles. The entire structure of the tree, from its leathery leaves to its complex fruit, reflects its long evolution in New Zealand's isolated forest ecosystems.
Quick Facts
| Scientific Name | Alectryon excelsus |
|---|---|
| Height | 7-12 m (occasionally up to 15 m) |
| Spread | 4-8 m |
| Water Needs | Moderate; prefers moist, well-drained soil |
| Light | Full sun to part shade |
| Frost Tolerance | Low; young trees are frost tender |
| Salt Tolerance | Moderate; tolerates coastal conditions |
| Growth Rate | Moderate |
| Lifespan | Long-lived (over 100 years) |
Climate Best Suited to
Alectryon excelsusis well adapted to various New Zealand regions.
Regional Suitability
| City | Climate Suitability |
|---|---|
| Auckland | High |
| Wellington | High |
| Christchurch | Medium |
Plant Habitat
Natural Occurrence and Ecology
Tītoki is widely distributed across the North Island and extends south to Banks Peninsula and central Westland in the South Island. It is a specialist of coastal and lowland forest environments, typically found from sea level up to 600 meters. The species thrives in moist, fertile sites, particularly on alluvial river flats, sandy plains, and sheltered coastal cliffs. It is a common component of the lowland canopy, often growing alongside other major forest trees like taraire, rimu, and northern rata. It shows a preference for comparatively warm, temperate situations where it is protected from extreme, repeated frosts, although mature trees develop significant resilience to maritime winds and coastal conditions.
Growing Requirements
Soil Requirements
Prefers well-draining soil rich in organic matter.
- Well-drained
- Loamy
Light Requirements
Grows best in partial to full sun.
- Full Sun
- Partial Shade
Water Requirements
Requires regular watering during dry periods.
- Regular
- Drought tolerant once established
Planting and Establishing
Establishment Guidance
Establishing Tītoki in a garden requires selecting a site that provides moist, well-drained, and fertile soil. It performs best in a position with full sun to partial shade, where the light can highlight its glossy foliage. While mature trees are quite hardy, young saplings are frost-tender and must be protected during their first few winters. Dig a hole twice the width of the root ball and enrich the soil with organic compost. Provide consistent watering during the establishment phase and during any prolonged summer dry spells to help the tree develop its deep, stable root system. Once established, Tītoki is remarkably drought-tolerant and resilient to wind, making it an excellent choice for North Island garden landscapes.
Ecological Role
Biodiversity and Ecosystem Impact
In its native forest ecosystems, Alectryon excelsus is a crucial keystone species that provides essential resources for a wide range of native fauna. Its bright red, fleshy arils are a vital food source for numerous native birds, including tūī, bellbird, kererū, and silvereye, which in turn act as the primary dispersal agents for the shiny black seeds. The nectar-rich flowers also attract a variety of native insects and pollinators. The tree's dense canopy provides excellent nesting and shelter sites for forest birds, while its extensive root system helps to mitigate soil erosion on river banks and coastal slopes. By contributing to the structural and biological complexity of the forest, Tītoki supports the overall health and stability of New Zealand's lowland ecosystems.
Uses & Significance
Garden Uses
Tītoki is one of New Zealand's most highly regarded native specimen trees for home gardens and urban spaces. Its rounded, spreading canopy provides excellent shade, while its glossy foliage and striking fruit offer year-round visual interest. It is ideal for inclusion in native forest-edge plantings or as a structural anchor in a larger garden border. The tree's tolerance for a range of conditions and its attractive form make it a popular choice for street planting and parklands. Because it is relatively slow-growing and responds well to careful pruning, it can be maintained at a manageable size for medium-sized properties, bringing a touch of native forest elegance to the suburban landscape.
- Specimen shade tree
- Coastal garden detail
Ecological Value
Ecologically, it is a key species for lowland forest restoration and riparian planting projects. It supports local biodiversity by providing high-energy food resources for native birds and pollinators, contributing to the creation of robust and self-sustaining native ecosystems.
- Bird food resource
- Erosion control
Landscaping Uses
In professional landscape design, Tītoki is used to add a sense of lush, evergreen permanence and refined structure. Its glossy olive-green leaves provide a sophisticated palette that contrasts beautifully with lighter green native shrubs and ferns. It is ideal for mass planting in parklands or used as a dramatic focal point in larger garden designs where its twisting trunk and architectural canopy can be fully showcased. The spectacular highlight of the red-arilled fruit in summer provides a unique seasonal interest. Its ability to withstand coastal conditions and wind while maintaining a tidy form makes it a versatile and highly effective choice for high-quality native landscaping across the North Island.
Seasonal Care Calendar
Spring
The start of the active growth surge. Apply a balanced slow-release native fertilizer or blood and bone around the drip line to encourage lush new foliage. Monitor young trees for any late spring frost damage.
- Fertilize
- Mulch
Summer
Ensure consistent moisture during hot, dry periods, as young Tītoki can be sensitive to severe drought. Mulching around the base will help keep the root zone cool and retain essential soil moisture while suppressing weeds.
- Water
- Check for pests
Autumn
The striking fruit mature and open during autumn, providing a feast for local birds. Tidy the area around the base and clear any heavy debris. This is a good time to prune for shape or to remove any crossing branches.
- Prune lightly
- Plant new specimens
Winter
Mature trees are hardy, but young saplings in frost-prone areas should be protected with frost cloth. Avoid any heavy root disturbance or changes to the soil level during the wet winter months to prevent root stress.
- Frost protection
When to Prune and How Much
Tītoki requires minimal pruning to maintain its naturally handsome form. Maintenance is generally limited to removing any dead, diseased, or damaged branches to improve airflow and overall tree health. If necessary, the canopy can be lightly thinned or shaped in late autumn to control the size or to showcase the architectural twisting of the main trunk. Always use sharp, sterilized pruning tools to ensure clean cuts that the tree can heal from quickly, reducing the risk of introducing fungal or bacterial pathogens. Young trees can be tip-pruned to encourage a denser, more rounded canopy if desired.
- Remove dead branches
Always use clean, sharp tools.
How to Grow Tītoki
Cultivating Tītoki (Alectryon excelsus) is a straightforward and rewarding process for any New Zealand gardener. This hardy native can be easily propagated through several methods, allowing you to add this iconic tree to your garden. Success depends on providing the warm, moist, and well-drained conditions it thrives in throughout its native lowland forest range.
From Seed
Propagation from seed is the most reliable method for Tītoki. Seeds should be collected as soon as the woody capsules split to reveal the bright red arils. The black seeds should be cleaned of the fleshy aril and sown immediately into a standard native seed-raising mix. They show good viability if sown fresh and generally germinate within 1-3 months. Keep the seedlings in a warm, sheltered spot with consistent moisture and protect them from direct midday sun during their first year.
Sow fresh seeds in a seed-raising mix.
- Collect seeds
- Sow in trays
Keep moist until germination.
From Cuttings
Vegetative propagation via semi-hardwood cuttings is also possible, though germination from seed is usually preferred. Take cuttings in late summer or early autumn and use a rooting hormone to encourage establishment. Place them in a well-drained cutting mix and maintain high humidity until new growth is evident. This method is ideal for ensuring new trees retain the desirable foliage characteristics of a specific parent plant.
Take semi-hardwood cuttings in late summer.
- Take cuttings
- Use rooting hormone
Additional Methods
Depending on the growth habit of Alectryon excelsus, other methods such as division or layering might also be viable options. Division is particularly suitable for plants that form dense clumps or have spreading root systems, while layering can be used for species with trailing or flexible stems.
Young Tītoki saplings are fast-growing but should be established in a sheltered site protected from strong winds and severe frosts. They require a site free from aggressive competition and benefit from regular mulching. Consistent watering during their first few summers is the key to ensuring these beautiful trees develop the deep, stable root system they need to become a permanent feature of the garden.
- Divide clumps
- Replant immediately
Pests & Diseases
Tītoki is remarkably resistant to most major garden pests and diseases once established. Its leathery, glossy leaves are seldom targeted by common insects. The primary risk is root rot, which can occur if the tree is planted in heavy, waterlogged soils with poor drainage. In some areas, introduced pests like possums can target the tender new growth or the mature seeds. Maintaining a healthy, well-nourished tree and selecting a well-drained planting site are the best preventative measures for ensuring the long-term health of your Tītoki.
Cultural Significance
The Tītoki holds deep cultural significance for Māori, recognized as a taonga of the lowland forest. The oil extracted from the shiny black seeds was historically a highly prized item, used as a fragrant skin moisturizer and for various ceremonial anointments. Its tough, elastic wood was valued for making handles for tools and implements. Today, the Tītoki stands as a powerful symbol of the resilience and unique beauty of New Zealand's indigenous flora, widely appreciated in modern gardens for its botanical and cultural heritage.
- Traditional medicine
- Crafts
Bonus Tip
To really see the spectacular red arils of Tītoki, plant the tree where it will be viewed from below or in a position that receives bright morning light. The sight of the brilliant red fruit bursting from their woody capsules against the dark green leaves is one of the true highlights of the New Zealand garden year.
Related Plants
Explore other native plants that share similar characteristics or habitats with Alectryon Excelsus ( Alectryon excelsus ), offering further insights into New Zealand's diverse flora. These related species provide context and opportunities for complementary planting in your garden.
Plant Conservation
Conservation Status
Currently classified as 'Not Threatened' nationally, Tītoki remains a stable and significant component of New Zealand's native forest flora. However, its long-term survival is linked to the preservation of lowland forest remnants and coastal habitats, which are increasingly threatened by development and land-use changes. Protecting these unique environments from the spread of invasive weeds and managing introduced pests like possums and rats are key strategies for ensuring this iconic tree continues to thrive across its natural range.