Tree to 22–30 m, 1 m dbh. Bark brown or reddish or greyish brown, scaly. Branchlets thick, greyish-black or brownish, glabrous or with web-like hairs when young; lenticels small but conspicuous, oblong. Buds large, elongated, oblong, greenish, 5-sided, with tomentose scales. Leaves evergreen, leathery, 6–12 × 2.5–4 cm, oblong to obovate, glabrous or covered with white silky hairs when young, becoming glabrous above with a floccose tomentum below that is soon lost, base slightly asymmetrically attenuate, obtuse or rounded, apex acute or shortly acuminate, margin upper half serrate with shallow, forward-pointing teeth; 8–12 secondary veins on each side of the midrib; petiole 1.5–3 cm long and glabrous. Infructescence 2–3.5 cm long with one to two cupules. Cupule cup-shaped to campanulate, 1–1.8 × 1.5–2 cm, outside brown velutinous, inside brownish or reddish tomentose; scales in 7 to 10 rings, only the inferior rings, closest to the twig, up to the fifth, are dentate or wavy. Acorn ovoid to cylindrical, with about half of its length enclosed in the cupule, 1.5–2.5 cm long, stylopodium persistent, ripening in the second year. (Liao 1996; Huang et al. 1999; le Hardÿ de Beaulieu & Lamant 2010).
Habitat Broadleaved evergreen forest between 600–2600 m (above 1500 m on Mount Ju), often forming pure stands.
USDA Hardiness Zone 9
RHS Hardiness Rating H3
Conservation status Least concern (LC)
This Taiwanese endemic oak was first introduced by the Edinburgh Taiwan Expedition of 1993 (ETE 11). One plant from this collection is recorded at RBG Edinburgh, and five at Foxhill Arboretum Cheshire, England (Royal Botanic Garden Edinburgh 2022). The Foxhill trees were sent there in the late 1990s but they have not been monitored since the early 2000s (T. Christian pers. comm. 2022). A tree grown at Tregrehan from seed received from Taiwan and planted in 2004 grew 2 m in the first two years and was 10 m plus tall in 2020 (T. Hudson pers. comm.).
A further introduction was made by Allen Coombes in 2003 (CMBS 642). Plants from this collection can be found at Buckingham Palace, where it was 3 m × 3.2 cm in 2020 (M. Lane pers. comm.); at Chevithorne Barton, England, where two trees were 3.5 and 7.5 m in 2021 (J. MacEwen pers.comm.); at RBG Edinburgh (Royal Botanic Garden Edinburgh 2022); and at Caerhays (Chassé 2017). In Continental Europe, the larger of two plants at Arboretum de la Bergerette, France, is of this collection and in 2021 was 3.8 m on three stems, the largest 7 cm diameter at 1 m (S. Haddock pers. comm.). There are two plants at Arboretum des Pouyouleix, France, the larger 1.2 m × 1.6 cm at 1 m (B. Chassé pers. comm. 2020). A tree at Arboretum Chocha, France was about 4 m tall in 2019, while at Iturraran Botanical Garden, Spain it was about 9 m tall in the same year (pers. obs.).
In North America the species has not had an easy time of it. There are two plants in the David C. Lam Asian Garden at the University of British Columbia, Canada of wild provenance from Taiwan; they had reached over 6 m in 2021 (University of British Columbia 2022, D. Justice pers. comm.). At the JC Raulston Arboretum in North Carolina, USA, however, Q. morii has proved to be one of the few evergreen oaks from Taiwan that has not survived, despite several attempts. The reason is not immediately apparent: one introduction was from acorns collected at over 2400 m elevation, so cold hardiness should not have been an issue. Plants tend to be lost in the nursery even before they are planted out (M. Weathington pers. comm. 2022). At nearby Plant Delights Nursery, an introduction from seed received from Taiwan Forestry Research Institute in 2004 was planted out in 2012 but had died by 2020 (Z. Hill pers. comm. 2022).
Allen Coombes recalls collecting this species in Taiwan in 2003 (CMBS 642). He was travelling between Tayuling and Wushe with staff from the Taiwan Forestry Research Institute after a few unproductive days. A loud crunching was heard under the wheels of the transport vehicle, and he immediately signalled the driver to stop. There were two 20-m trees at the roadside. The acorns were dropping off the trees and bouncing on the road before collecting in their hundreds in a ditch.
The epithet commemorates Ushinosuke Mori (1877–1926?), a Japanese anthropologist and folklorist, best known for his work studying the aborigines of Taiwan. For a time he was employed by the Japanese Governor General’s Office to collect and study plant samples, and together with Takiya Kawakami in 1906 he collected on Yushan (Mount Ju, formerly known in English as Mount Morrison) the specimen described by Hayata in 1911 (Ohashi 2009; Digital Taiwan – Culture & Nature 2022; Hayata 1911). The common name in Chinese can be translated as ‘Taiwan evergreen oak’.