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Article from New Trees by John Grimshaw & Ross Bayton
'Quercus insignis' from the website Trees and Shrubs Online (treesandshrubsonline.
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Tree to 30 m, 1.3 m dbh. Branchlets covered in dense, yellow to red tomentum; in the second year, becoming glabrous, glaucous or grey and with prominent white lenticels. Leaves deciduous, 10–20(–28) × 4–9(–10) cm, elliptic to obovate, thick and hard, upper surface shiny and glabrous, lower surface dull and tomentose, 18–20 secondary veins on each side of the midrib, margins entire or undulate, very rarely dentate, apex acute; petiole 0.8–1.5(–2.5) cm long, densely tomentose. Cupules one to four, sessile; saucer-shaped, 4–8 × 2–3 cm, often contracted at the base; scales large, free, golden-tomentose, broad and triangular at base of cupule, narrow and inward-curving at margins, tomentose or almost glabrous, tips appressed or spreading. Acorn ovoid to globose, with half to two-thirds of its length enclosed in the cupule, 3–5 cm long, to 12 cm diameter, stylo-podium short; basal scar prominent, and golden, silky hairs at apex. Fruiting July to August (Costa Rica). Muller 1942. Distribution COSTA RICA; GUATEMALA; HONDURAS; MEXICO: Jalisco, Oaxaca, Veracruz; PANAMA. Habitat Cloud forest between 900 and 2000 m asl. USDA Hardiness Zone (9–)10. Conservation status Near Threatened (IUCN); endangered in Mexico, due to habitat loss. Illustration NT35, NT698.
According to Rodriguez-Coombes et al. (2004), Quercus insignis is one of the most spectacular trees in Mexico, but it is threatened by forest clearance for coffee cultivation. This should serve as a hint that it is a very tender species – not surprising for a primarily Central American tree with only limited occurrence in Mexico. It has grown happily outside for several years in the collection of Michel Duhart, Arboretum Chocha, near Ustaritz, in the Pyrénées Atlantiques, France (A. Coombes, pers. comm. 2006), and Thomas Methuen-Campbell has a 1.5 m specimen in similar coastal conditions at Penrice Castle in south Wales – although this is protected in winter (A. Coombes, pers. comm. 2008). In general, however, where it has been tried outside in the United Kingdom it barely survives. Showing what it can do, there is a most impressive specimen in the Temperate House at Kew, touching the roof seven years after planting in 1998. This was grown from material collected by Allen Coombes (no. 221) near Huatusco, Veracruz in 1995. Its large bold foliage, flushed bronze when young (with new shoots being produced even in winter), would be good reason enough to try to grow it, but the most exciting character of this species is the huge size of the acorns, which can be an extraordinary 10–12 cm across (excluding the cupule). Another unusual feature is that the hypocotyl emerges from the base of the acorn – a distinction otherwise known only in Q. alnifolia and Q. aucheri from the eastern Mediterranean (A. Coombes, E. Jablonski, pers. comms. 2006).