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Article from New Trees by John Grimshaw & Ross Bayton
'Quercus ellipsoidalis' from the website Trees and Shrubs Online (treesandshrubsonline.
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Tree to 20 m, 1.5 m dbh. Bark thin, greyish brown, divided into thin plates by shallow fissures. Crown narrow, oblong, with many forked branches; stumps of dead branches often prominent at the base of the trunk. Branchlets dark reddish brown and glabrous. Leaves deciduous, 7–13 × 5–10 cm, elliptic to obovate, glabrous, though lower surface often has tufts of hair in the vein axils, three to four secondary veins on each side of the midrib, margins with five to seven deep lobes, lobes largely oblong, expanding distally and terminating in spiny bristles (15–55 in total), median lobes longer than other lobes, lobe sinuses over half the distance to the midrib, apex acute; petiole 2–5 cm long, glabrous. Cupule turbinate or deeply cup-shaped, 1–1.9 × 0.6–1.1 cm, outer surface reddish brown and slightly pubescent, inner surface light brown and glab rous; scales obtuse or acute, apices tightly appressed. Acorn broadly ovoid to ellipsoid, with one-third to half of its length enclosed in the cupule, 1–2 cm long, stylopodium may be surrounded by several faint rings. Flowering May, fruiting August of the following year (USA). Nixon 1997. Distribution CANADA: Ontario; USA: Illinois, Indiana, Iowa, Michigan, Minnesota, Ohio, Wisconsin. Habitat Limestone ridges and slopes, dry sandy sites and along small streams between 150 and 500 m asl. USDA Hardiness Zone 4. Conservation status Least Concern. Illustration Nixon 1997; NT9, NT719. Cross-references B499, S414, K86. Taxonomic note This species may be of hybrid origin (Jensen et al. 1984).
Briefly described by Bean (1976b), who mentions a moderately sized tree at the Royal Botanic Garden Edinburgh, Quercus ellipsoidalis is a species that has since become only slightly better known in Europe. It is apparently not greatly valued in North America either (Sternberg 2004), although one tree collected by C.S. Sargent is still growing at the Arnold Arboretum and it is in most collections, including good specimens at the Morton Arboretum. The old Edinburgh tree still survives, and has been joined by two more recent plantings. One of these, accessioned in 1985 and now 8 m in height, has been badly damaged by Grey Squirrels and its trunk is covered in scars from their depredations. Specimens in southern England seem to have avoided this fate, and the largest ones observed for the present work, at the Hillier Gardens, are fine upright trees. One of these, sited near Brentry House, is apparently an unrecognised champion, measured in 2001 at 18.4 m (Sir Harold Hillier Gardens database) – the official champion being a tree at Borde Hill planted in 1935, 17 m in 1995 (Johnson 2003). When these trees are given plenty of space they have a tend ency to develop wide-spreading branches to form a rounded crown. An individual at Kew, donated in 1974 by J.R.P. van Hoey Smith, is currently c.10 m tall and as much wide, with a dbh of 32 cm. This and another specimen at Kew coloured to a rich tan-brown in 2005 (a poor year for autumn colour in England), with the leaves hanging dry on the tree to great effect, but a brighter red can usually be expected; Sternberg (2004) notes the exceptional red autumnal colouring of this species, while Hillier & Coombes (2002) regard it as equal to the best forms of Q. coccinea. The cultivar ‘Hemelrijk’ has been propagated from a tree at the de Belder property noted for its reliable brilliant red colours in autumn, and the habit of retaining its tan leaves all winter. In spring the young leaves emerge pink, and then become an attractive deep green. ‘Hemelrijk’ was selected by Robert and Jelena de Belder in about 1980, and introduced to the nursery trade by M.M. Bömer, Zundert, the Netherlands (J. Bömer, pers. comm. 2006). Quercus ellipsoidalis is regarded as a calcifuge (Hillier & Coombes 2002), and at Kruchten succumbs to chlorosis at pH 6.8.