Phyllocladus trichomanoides
Sponsor
Kindly sponsored by
members of the RHS Woody Expert Group
in memory of Seamus O'Brien (1970-2025).
Credits
Tom Christian (2026)
Recommended citation
Christian, T. (2026), 'Phyllocladus trichomanoides' from the website Trees and Shrubs Online (treesandshrubsonline.
Common Names
- tānekaha
Infraspecifics
Trees to >20 m tall in forests, to 1 m dbh with a clear bole to 10 m or more. True leaves on seedlings 10–15 mm long, to 1 mm wide, filiform; subulate deciduous leaves 1–4 mm long may appear at base of phylloclades and on their margins in young plants. Phylloclades pinnately compound or pinnatifid (least dissected on old trees), pinnate segments bifacially flattened, leaf-like, (0.5–)2–8(–12) mm long, more or less rhombic in outline, margins crenate to obtusely lobed. Flushing phylloclades bright green or with a reddish hue, turning dark green above, pale green below, sometimes glaucous. Pollen cones borne from terminal buds in pseudo-whorls of up to 10 cones, each on a 5–10 mm long peduncle or sessile, subtended by one or two spathulate bracts, pollen cones cylindrical, 8–10 × 2.5–3 mm, purple or reddish at first, ripening red-brown with yellow pollen. Seed cones axillary to reduced and deciduous scale leaves on the margin or apex of reduced phylloclade segments, or at base of undivided phylloclades, solitary or up to 4 together, each consisting of several bracts, 2–3 of which are fertile and merge to a reddish or purplish-green structure 3–5 mm long, which becomes somewhat swollen and purple (drying brown). Seeds 1 per fertile bract, 2–3 per cone, each in a white aril covering the lower two-thirds or more of the seed, 5 mm long, semi-ovoid (laterally flattened) with a ridge, greenish-black. (Farjon 2017).
Distribution New Zealand North Island, South Island
USDA Hardiness Zone 9b-11a
RHS Hardiness Rating H3
Conservation status Least concern (LC)
Taxonomic note Some works recognise a variety, P. trichomanoides var. alpinus, but we follow the view of most New Zealand botanists and treat this taxon at species rank, viz. Phyllocladus alpinus.
This New Zealand species was discovered for modern botany by Banks and Solander during Captain Cook’s first voyage (1768–1771). Of course it had been known to the Māoris for some time, who extracted dyes from the bark and found various uses for its white, close-grained, strong wood. European settlers would later use the timber for piles and mine props, while large quantities of bark were exported to Europe for dyeing and tanning (Bean 1976; Kent 1900).
As with all Phyllocladus there is no record of exactly when P. trichomanoides was introduced to European cultivation, but it began to appear in nursery catalogues in the middle of the 19th century and was perhaps in specialist collections such as Kew a few decades prior. W.J. Bean described it as being ‘hardy in Cornwall, the south of Ireland, and in similar places’ (Bean 1976). Nearly all of the nineteen examples recorded on the public-facing database of the Tree Register of Britain and Ireland in 2026 are restricted to these areas, including the tallest, 14 m in the walled garden at Mount Usher, Wicklow, Ireland in 2015, and the largest, 54 cm dbh at Fota, Cork, Ireland (pictured below). Two dissenters include a tree planted in the Heather Garden in Windsor Great Park in 2018, 2.3 m tall and ‘growing well’ in 2021, and another in the garden in Buckingham Palace, London, 5 m tall in 2021 (The Tree Register 2026). No confirmed specimens were traced in North America during research for this account; it is likely that those areas wet enough for it still experience colder winters than it will tolerate.
Certainly Phyllocladus trichomanoides is significantly less hardy than P. alpinus, which replaces it at altitude and in the far south of New Zealand, though it is able to withstand a few degrees of frost and the H2 rating (1–5°C, tender; cool or frost-free glasshouse) given by the RHS and repeated in various publications is unduly conservative (pers. obs.). We suggest H3 (–5–1°C, half-hardy; needs unheated glasshouse or mild/coastal winter) though for plants outdoors supplementary protection in their first few winters is advised. Where it grows well this is a handsome curiosity and a talking point, well worthy of greater experimentation.
'Silver Blades'
A form with glaucous phylloclades raised by the Hillier Nurseries, UK, and put into commerce by them in 1968. An old plant, perhaps an original, was still growing in the Brentry area of the Sir Harold Hillier Gardens in 2017 when it measured 9.7 m tall × 11 cm dbh (The Tree Register 2026), more recently it has been described as ‘still surviving, just’ (R. White, pers. comm. 2026). ‘Silver Blades’ has always been something of a disappointment in the UK, which has fuelled speculation this is a form of P. trichomanoides and not the much hardier P. alpinus, a species which would not be expected to reach the dimensions of the Hillier example. The modern glaucous P. alpinus selections are superior in the UK climate, especially ‘Blue Blades’.