Pseudopanax is a genus of evergreen trees and shrubs in the family Araliaceae (order Apiales), endemic to New Zealand. The genus is best known for species that display dramatically different juvenile and adult growth forms — young plants bear long, narrow, stiffly toothed leaves, while mature plants develop broader, softer foliage, a strategy thought to be an adaptation against browsing by the now-extinct moa. The most iconic examples are Pseudopanax crassifolius (lancewood) and Pseudopanax ferox (toothed lancewood), both striking architectural trees valued in horticulture for their sculptural silhouettes.
Pseudopanax flowers are borne in terminal umbels, characteristic of the Araliaceae family. The genus was formerly broader but a 2000 molecular study revealed that several species were only distantly related to the core New Zealand group centred on the type species P. crassifolius; those species were subsequently transferred to the segregate genus Raukaua.
Species occur in forest and scrub environments throughout New Zealand. Several, particularly Pseudopanax lessonii, are popular in New Zealand gardens and have yielded ornamental cultivars such as 'Gold Splash' (yellow-variegated leaves) and 'Nigra' (dark purple-brown foliage). Cultivation outside New Zealand is possible in mild, moist climates — including parts of Southern California and the warmer regions of Great Britain — but the genus does not tolerate temperature extremes well.
Etymology
The name Pseudopanax derives from Latin and Greek: pseudo- meaning "false" and Panax (ginseng), reflecting the genus's superficial resemblance to true ginseng relatives in the Araliaceae family — hence "false ginseng."
Distribution
Pseudopanax is endemic to New Zealand, where species grow in forest and scrub habitats across the country. The genus does not occur naturally outside New Zealand.
Ecology
Species of Pseudopanax inhabit forest and scrub environments in New Zealand. Several species — most famously P. crassifolius and P. ferox — display dramatically heterophyllous growth: juvenile plants bear long, narrow, downward-angled leaves with serrated margins, while adult plants produce quite different broader foliage. This striking developmental change is widely interpreted as a defence adaptation against browsing pressure from the extinct moa (Dinornis spp.) and other large ratites that once shaped New Zealand's vegetation.
Cultivation
Many Pseudopanax species are grown as ornamental plants in New Zealand gardens. Outside New Zealand they require mild, moist conditions without harsh temperature extremes; good results have been reported in Southern California and the warmer parts of Great Britain. Pseudopanax lessonii is the most commonly cultivated species and has given rise to several named cultivars, including 'Gold Splash' (yellow-variegated leaves) and 'Nigra' (dark purple-brown foliage). A notable specimen of P. crassifolius at the Alton property, Mount Macedon, Victoria, Australia — listed by the National Trust — stands 21 metres tall with an 11.5 m spread and is estimated to be about 100 years old.
Taxonomy Notes
Pseudopanax was historically a broader genus, but a molecular phylogenetic study published in 2000 demonstrated that several included species were only distantly related to the core New Zealand group centred on the type species P. crassifolius. Those outlying species were transferred to the reinstated genus Raukaua, reducing Pseudopanax to its current circumscription of closely related New Zealand endemics. The genus belongs to the family Araliaceae, order Apiales.
