Synonym Alsophila smithii Epithet is after John Smith (1798-1888). Evergreen, 25 ft. (7.5 m). Zones 9 and 10.
description: The brown trunk reaches 25 ft. (7.5 m) and is surrounded just below the crown by skirts of dead frond
midribs that offer protective insulation from winter cold. Soft green, tripinnate fronds are 7 to 9 ft. (2.1 to 2.7 m) long and have abundant brown scales along the stipes. Sori with saucer-shaped indusia are on both sides of the pinnae midrib.
range and habitat: This species, the most southerly growing of the world's tree ferns, is native to high elevations in New Zealand and as far south as the Auckland Islands. It prefers wet cold forests and thrives right up to the snow line of the glaciers on New Zealand's South Island. As life insurance, it produces a chemical that when dispersed can inhibit the root growth of competing plants.
culture and comments: Like most tree ferns, it needs hu-musy soil and an overstory of protective trees, plus shelter from wind and prolonged frost. It would make a good trial plant for hardiness in the warmer regions of Zone 8 with, of course, the requisite winter protection.
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