D. dacrydioides is a dioecious specimen forest tree with fast growth to five metres within ten years up to an average maximum of forty metres. It carries mature khaki green foliage barely recognisable as leaves, partly because of the great height at which they grow, but also because their overlapping form is almost scale-like. Seedling and sapling leaves are soft, crescent-shaped, with pointed tips. Kahikatea are more often defined by their greyish-brown bark, which in mature trees sheds small scales, giving the tree the appearance of having been crafted with a hammer. They need good light, and their upright narrow conical crowns protrude through the canopy to access it.
Flowering occurs from October through January with single dark green male flowers appearing at the end of branchlets. Minute female flowers are borne on separate trees when pollen is released from October to November. Once fertilised the female bloom enlarges and forms a 6mm round pulpous fruit with a glossy dark nut on the crown. Fruit ripens over a year to bright orange from February to April. Open-grown trees lush with ripe fruit are exceedingly attractive. In a good seed year which can be four years apart, a single tree can produce 135kg of fruit (4.5 million seeds) making Kahikatea an important food source for frugivores, particularly kereru, bellbird, and waxeyes, but also blackbirds and thrushes. Birds are the primary mode of seed dispersal.
This hardy conifer loves swampy and riparian situations but also thrives in high rainfall regions on well-drained hill sites up to 700m altitude in the North Island, 500m in the South Island, and close to sea level on Stewart Island. On swampy sites D. dacrydioides develops flanges and buttresses for stability which extend to the roots. This native is frost-tolerant.
Kahikatea makes a magnificent statement tree in large parks with riparian margins or other open environments and does well planted in stands.
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