Sciadopitys verticillata (Thunb.) Siebold & Zucc. (Sciadopityaceae)


Japanese umbrella pine

Habit of the Japanese umbrella pine in the Harcourt Arboretum. Arrangement of Sciadopitys verticillata cladodes.

The Japanese umbrella pine, a conifer to endemic Japan, is the sole extant member of the distinctive family Sciadopityaceae. The generic name is Greek for 'umbrella pine', and is a reference to the whorls of leaf-like, photosynthetic stems that surround the branches.

With an altitudinal range of 200-1700 m, Sciadopitys is distributed across the Japanese archipelago, from Honshu in the north to Shikoku and Kyushu in the south. Typically, this conifer forms part of Japanese mixed conifer-broadleaved forests. Sciadopitys can often be found as solitary trees, or in small groves. In the case of the latter, and a reflection of successional recruitment stages, these groves are more or less pure. A recent seed collecting expedition undertaken by Oxford Botanic Garden and Harcourt Arboretum noted that small populations were found more commonly in rocky, cool and moist ravines and valleys.

Past logging and subsequent conversion of forests to planted monocultures has not only led to restricted occurrences in many regions, but has also contributed to the tree's IUCN Red List Status of Near Threatened. A recent global reassessment of the conservation status of the world's conifers has highlighted that 34% are globally threatened with extinction. Supported through the International Conifer Conservation Programme, the umbrella pine is safeguarded in 156 ex situ collections.

Over the years, the durability of umbrella pine's timber has made it attractive for construction, and to a lesser extent, boat and furniture building. However, Sciadopitys' most valuable commercial use has been its adoption by the horticultural trade. Unperturbed by its slow growth rates, this very attractive conifer can be found in a wide range of settings across Japan, from the bustling urban environment to the tranquility of a traditional Japanese garden. Less commonly, the umbrella pine can be found in gardens and collections in the USA and across Europe. The umbrella pine was introduced into the UK in 1860 by the Victorian botanical explorer of Japan, John Veitch.

There are two specimens at Harcourt Arboretum; the larger of the two is situated a short walk, on the left-hand side, along the Serpentine Ride. Despite looking very content with its location, having clearly thrived since being planted in 1963, it started its life in a pot at the Botanic Garden, housed in the conservatory. The former Superintendent of the Botanic Garden, Ken Burras, brought the plant to Harcourt when the arboretum was acquired by the Botanic Garden in 1963.

Further reading

Shaw K and Hird A 2014. Global survey of ex situ conifer collections. BGCI.

Farjon A 2008. A natural history of conifers. Timber Press.

Ben Jones