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Article from New Trees by John Grimshaw & Ross Bayton
'Quercus oglethorpensis' from the website Trees and Shrubs Online (treesandshrubsonline.
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Tree to 25 m. Bark pale grey or light brown and scaly; epicormic shoots from the trunk are frequent. Branchlets initially covered with stellate hairs, later reddish brown and largely glabrous. Leaves deciduous, 5–15 × 2–4.5 cm, elliptic to oblanceolate, immature leaves with short-stalked red glands above and sparse stellate hairs below, mature leaves dark glossy green above, yellowish green and thinly covered in stellate hairs below, three to eight secondary veins on each side of the midrib, margins entire or with a few teeth towards the apex, apex rounded, obtuse or acute; petiole 0.2–0.7 cm long. Infructescence with one to two cupules. Cupule turbinate, 1 × 0.8 cm; scales pale brown-pubescent and closely appressed. Acorn ovoid, with one-third of its length enclosed in the cupule, 0.9–1.1 cm long, stylopodium short. Flowering April (USA). Coombes & Coates 1995, Nixon 1997. Distribution USA: Georgia, Louisiana (?), Mississippi, South Carolina. Habitat Alluvial woodland and pasture between 0 and 200 m asl. USDA Hardiness Zone 5. Conservation status Endangered. Quercus oglethorpensis has a restricted range and is threatened by chestnut blight and poor seed viability. Illustration Coombes & Coates 1995, Nixon 1997; NT743.
A fascinating, discursive account of General James Oglethorpe and the oak that obliquely commemorates him through its occurrence in Oglethorpe Co., Georgia has been given by Coombes & Coates (1995 in The New Plantsman, reprinted 1996 in the Journal of the International Oak Society). Although the authors of this account were somewhat pessimistic about the chances of this white oak in northern Europe, it must be said that, while not flourishing in the same way as some of the new Mexican introductions, Quercus oglethorpensis is making reasonable trees in southern England, and is growing steadily though slowly in Luxembourg (E. Jablonski, pers. comm. 2006); also at Arboretum de la Bergerette, where it has achieved 4 m in 10 years with no twig dieback (S. Haddock, pers. comm. 2006). Coombes & Coates recorded, in 1995, that the biggest specimens at the Hillier Gardens were 3.5 m tall, but the largest there now (the UK champion, grafted on Q. robur in 1978) is 8.9 m tall (2008), and seedlings from 1989 have reached 5 m. The new growth, especially from the many epicormic shoots on trunk and branches, often fails to ripen in the cool English summers, and there is much annual dieback of smaller shoots, giving a somewhat unshaven appearance to what would otherwise be a more respectable tree. In the warmer summers of the eastern United States Q. oglethorpensis fares much better, even as far north as Illinois (Coombes & Coates 1995, Sternberg 2004). Exemplifying this are several specimens at the Morton Arboretum which have made rounded crowns as broad as they are high (8–9 m) and look very happy, with dense canopies of glossy dark green leaves. They are very densely branched, with minimal twig dieback.