New Zealand Laurel (Pukatea)

Basic Information

Common Name: New Zealand Laurel (Pukatea)
Scientific Name: Laurelia novae-zelandiae
Native Habitat: Native to New Zealand, found in lowland forests, often in swampy areas, damp gullies, and along stream banks throughout the North Island and the northern parts of the South Island.

History / Discovery / Cultivator

Laurelia novae-zelandiae, commonly known as Pukatea or New Zealand Laurel, is a tree deeply woven into the ecological and cultural tapestry of New Zealand. It belongs to the small family Atherospermataceae, a group of aromatic evergreen trees and shrubs predominantly found in the Southern Hemisphere, particularly in Australasia and South America. The specific name “novae-zelandiae” directly translates to “of New Zealand,” referencing its exclusive native range.

The scientific description of Pukatea is credited to French botanist Achille Richard in 1832. Richard was part of the scientific team aboard the Astrolabe, a French expedition led by Jules Dumont d’Urville that explored parts of the Pacific, including New Zealand, in the late 1820s. While European science formally cataloged the species in the early 19th century, the tree had been known and utilized by the indigenous Māori people for centuries prior to European arrival.

The Māori name, Pukatea, is indicative of its traditional importance. The inner bark has been historically used for medicinal purposes, particularly for its analgesic and anti-inflammatory properties. It contains alkaloids, notably pukateine, which have been the subject of scientific study for their pharmacological effects. The timber, while relatively soft, is lightweight and durable under certain conditions, historically used for purposes like boat building, particularly for the upper parts of canoes (waka), due to its resilience to rot when kept wet. Its distinctive buttress roots were also noted and utilized in traditional Māori life.

European settlers, upon arriving in New Zealand, also recognized the tree and its timber, though perhaps less extensively than other native species like Kauri or Totara. The timber found some use in general construction where lightness and moderate durability were required, especially in damp environments. However, it was not as widely exploited for large-scale logging as some of the more structurally robust hardwoods.

Cultivation of Pukatea, particularly outside its native range, is not widespread. Within New Zealand, it is sometimes planted in parks or large gardens, valued for its attractive buttress roots, glossy foliage, and ecological role. Its preference for wet or swampy ground limits its suitability for typical garden settings unless specific conditions can be provided. Unlike many ornamental plants popularized globally by horticulturalists in the 19th and 20th centuries, Pukatea has remained largely a species of regional interest, primarily valued within New Zealand for its ecological importance in wetland forests and its cultural significance to Māori. Its unique adaptations to waterlogged soils, including specialized root systems that facilitate oxygen uptake, make it a fascinating subject for botanical study, further contributing to its recognition within scientific circles if not broader popular horticulture.

Over time, as conservation efforts have gained prominence, native species like Pukatea have been increasingly appreciated for their role in riparian and wetland ecosystems. Restoration planting projects often include Pukatea to help stabilize stream banks and restore biodiversity in degraded wet forest areas. Thus, while not a globally cultivated ornamental, Pukatea holds significant value within its homeland – a value rooted in its ecological niche, traditional use, and unique botanical features.

Plant Care Summary

Botanical Insights

Adaptations

Pukatea is renowned for its striking plank-like buttress roots, which can spread widely from the base of the trunk. These buttresses are a key adaptation to its preferred habitat of waterlogged or swampy ground. They provide structural support in unstable, soft soil and are also believed to aid in aeration, allowing the roots to access oxygen in anaerobic conditions. The tree’s ability to tolerate prolonged periods with its roots in water is a significant adaptation distinguishing it from many other tree species. Its thick, glossy leaves are resistant to wilting and desiccation. The flowers are small and inconspicuous, adapted for wind pollination.

Propagation Methods

Propagation of Pukatea is primarily done from seed. Fresh seeds germinate relatively easily if kept moist and provided with suitable conditions. Vegetative propagation methods like cuttings can be more challenging for this species compared to others, often requiring specific techniques like mist propagation and hormone treatments for success, particularly with mature wood cuttings. Air layering is also sometimes attempted but is not as commonly successful as seed propagation.

Toxicology

Laurelia novae-zelandiae contains significant levels of isoquinoline alkaloids, the most notable being pukateine. These compounds are toxic if ingested. Pukateine has been studied for its pharmacological effects, including analgesic properties, but is associated with potential adverse effects on the central nervous system. Ingestion by humans or pets is not advised and could lead to symptoms related to alkaloid poisoning, which can include gastrointestinal upset, dizziness, or more severe neurological effects depending on the amount ingested. Due to the presence of these toxic compounds, Pukatea should be kept out of reach of children and pets.

Common Problems

Pests:

• Scale insects
• Aphids
• Mealybugs

Diseases:

• Root rot (especially if soil conditions are not consistently wet but alternate between wet and dry, or if drainage is poor in an unsuitable location)
• Various fungal leaf spots (less common but can occur in very damp, shaded conditions)

Other:

• Nutrient deficiencies (can occur in highly leached or poor soils; indicated by yellowing leaves)
• Frost damage (young trees are susceptible to damage from hard frosts)
• Failure to thrive (often due to insufficient water or planting in unsuitable, dry soil)

Rarity & Value

Rarity:

Laurelia novae-zelandiae is not considered a threatened species in its native range and is relatively common in suitable habitats throughout the North Island and northern South Island of New Zealand. Its ‘rarity’ is more geographical, being confined naturally to New Zealand. Outside of New Zealand botanical gardens or specialist collections, it is rare in cultivation simply because it is not widely grown or traded internationally, partly due to its specific habitat requirements (liking wet feet) and lack of significant ornamental appeal compared to more showy flowering or foliage plants. Variegated forms or specific desirable cultivars are not widely known, which limits interest from collectors seeking novel mutations.

Value:

The value of a Pukatea specimen is typically assessed within its native context or for ecological/botanical purposes rather than as a highly prized ornamental plant on the international market.

• Ecological Value: High value in its native habitat for contributing to wetland ecosystems, providing habitat, and stabilizing stream banks.
• Cultural Value: Significant historical and medicinal value to Māori people.
• Timber Value: Moderate value for specific uses where lightweight, water-resistant timber is needed, though not a high-value timber for general construction.
• Horticultural/Market Value (outside NZ): Generally low on the international market due to low demand, specific growing requirements, and limited ornamental appeal compared to more popular species. A mature specimen with impressive buttress roots might have some value for landscaping in suitable climates, but commercial propagation and sale are limited. Value in cultivation is primarily tied to its botanical interest and uniqueness as a New Zealand native.