Tetrapanax papyrifer, the rice paper plant (通草—tong cao), is an evergreen shrub or small tree in the family Araliaceae, the sole species in the genus Tetrapanax.[1] [2] The specific epithet is frequently misspelled as "papyriferum", "papyriferus", or "papyrifera". It is native to eastern and central China and Taiwan, but widely cultivated in East Asia and in other tropical[3] to mild temperate regions as well.
The species was first described in the genus Aralia as Aralia papyrifera, and has also been treated in Fatsia as Fatsia papyrifera.[4]
A second species, Tetrapanax tibetanus, is now regarded as a synonym of Merrilliopanax alpinus.[5]
Tetrapanax grows between 3–7 metres tall, with usually unbranched stems 2–9 cm in diameter, and bearing a rosette of large leaves atop the crown; the top of the plant can visually, albeit superficially, appear similar to a number of plants belonging to Arecaceae (the palm family). The leaves are carried on 40–60 cm petioles; the orbicular leaf blade measures from 50 to 75 cm across (to a metre across in some cultivars), with anywhere from 5-12 deeply incised palmate lobes, the central lobes being larger and Y-forked near the end. It spreads extensively, by sprouts and runners from the root system, underground. The inflorescence is a large panicle of hemispherical or globular umbels, at the end of the stem. The flowers have 4-6 small, white petals. The fruit is a small berry 4 mm in diameter.
Tetrapanax papyrifer is used in traditional Chinese medicine. The pith from the stem is used to make a substance commonly known as rice paper,[4] but more properly termed pith paper.
The species is cultivated as an ornamental specimen plant, and has received the Royal Horticultural Society's Award of Garden Merit.[6]
The cultivar 'Rex' is a semi-evergreen shrub or tree with huge palmate leaves up to a metre diameter. Classified by the Royal Horticultural Society as H4, it is evergreen in mild locations, deciduous where temperatures fall below freezing, and herbaceous with more prolonged freezing. It prefers a sheltered position in full sun or partial shade.[7]