September in the hills with Chris Horne and Barbara Mitcalfe
Phyllocladus trichomanoides, tānekaha, celery pine
We focus on tānekaha, the largest of the three species in the Phyllocladus genus, then briefly describe the other two members of the genus.
When you see tanekaha, you will realise that its common name, ‘celery pine’, is an apt description. What look like oddly-shaped leaves are, in fact, flattened branchlets called phylloclades, which function as leaves. Hence the name Phyllocladus, which means leaf-like branches, making the members of this genus unique among our endemic conifers.
Tanekaha grows in lowland forest up to 800 m elevation; in the North Island, from North Cape to Whanganui and Waipukurau, and in the South Island, in northern Marlborough, Nelson and Buller. It is a graceful, pyramidal tree up to 20 m tall, with a trunk up to 1 m diameter, with smooth, grey-brown bark, usually covered with lichens. Often it has no branches for the first 6 m, above which slender branches radiate from the trunk horizontally.
A fascinating feature is that seedling tānekaha do have real leaves which are up to 20 mm long, reddish-brown, narrow, parallel-sided, and deciduous. These are replaced by the phylloclades, which are diamond-shaped to fan-shaped, lobed, 15-25 x 10-15 mm, and arranged in two rows.
Tanekaha is monoecious, so both female and male cones appear on the same tree. Clustered at the tips of the branches, the stalked male pollen cones (c. 10 mm long), dark purple when young and crimson when mature, produce pollen which the wind carries to the blue-purple female seed cones, (c. 3 mm diameter), developing at the margins of the phylloclades. Each cone will produce a seed.
To dye harakeke / flax mats and korowai / cloaks, red-brown, Māori pulped the bark, added water, threw in hot rocks to boil the mixture, then soaked the items in it. They used the tannin-rich bark to tan nets, and as a rongoā, to control dysentery. In the 19th century, the bark was exported to Germany to make red and pink dyes. Spinners still use it for dyeing, producing a wide range of colours, depending on the mordant used. The strong, durable wood has had many uses, including threshing machines, mine props, bridges, fish hooks, and, because the wood is so flexible, walking sticks and fishing rods.
Related Phyllocladus species
Phyllocladus toatoa, toatoa, grows from sea level to 600 m elevation, from Te Paki south to Awakino in the west, and Lake Waikaremoana in the east. It is a tree up to 15 m tall, with a trunk up to 60 cm diameter, and smooth, grey bark. The wedge-shaped, leathery phylloclades, 40-60 x 20-40 mm, are sea-green when young and bronze-coloured when mature. This species can be monoecious or dioecious.
Phyllocladus alpinus, mountain toatoa, grows in the North Island in subalpine forest and scrub, from 900-1600 m elevation, usually on or near the upper margins of beech forest, from Coromandel Peninsula southwards, including the Tararua Range, (except Mt Taranaki). In the South Island, in the west, it grows down to sea level. A shrub, or tree up to 9 m tall, it has a trunk up to 40 cm diameter, with smooth, grey bark. Unlike the two species above, the phylloclades, 5-25 x 3-12 mm, are attached to ordinary twigs, and usually greyish. This species is monoecious.