Quercus germana Schltdl. & Cham.

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Credits

Article from New Trees by John Grimshaw & Ross Bayton

Recommended citation
'Quercus germana' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/quercus/quercus-germana/). Accessed 2024-03-19.

Genus

  • Quercus
  • Subgen. Quercus, Sect. Quercus

Common Names

  • Avocado-leaf Oak
  • Mexican Royal Oak

Synonyms

  • Q. galeottii M. Martens & Galeotti

Other taxa in genus

Glossary

dbh
Diameter (of trunk) at breast height. Breast height is defined as 4.5 feet (1.37 m) above the ground.
flush
Coordinated growth of leaves or flowers. Such new growth is often a different colour to mature foliage.
pubescent
Covered in hairs.

References

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Credits

Article from New Trees by John Grimshaw & Ross Bayton

Recommended citation
'Quercus germana' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/quercus/quercus-germana/). Accessed 2024-03-19.

Ultimate height and girth unknown. Branchlets pale grey-brown, slender and glabrous. Leaves deciduous, 9–13 × 3–5 cm, oblong to obovate or oblanceolate, largely glabrous and glaucous below, immature leaves bright pinkish purple, six to eight secondary veins on each side of the midrib, margins crenate to sinuate with 6–12 lobes in the upper third of the leaf, apex obtuse; petiole 0.2–0.5 cm long and glabrous. Infructescence 1–1.5 cm long with one cupule. Cupule hemispheric, 1.8–2.5 × 1.2 cm, outside rusty- or grey-tomentose; scales acute, keeled and appressed. Acorn subglobose, rusty-tomentose, with three-quarters of its length enclosed in the cupule, 2 cm long, stylopodium prominent. Standley 1922, Trelease 1924. Distribution MEXICO: Hidalgo, Oaxaca, Puebla, San Luis Potosí, Tamaulipas, Veracruz. Habitat Montane cloud forest between 800 and 1800 m asl. USDA Hardiness Zone 8–9. Conservation status Vulnerable, due to habitat loss. Illustration NT726. Taxonomic note Trelease (1924) recognised specimens in Veracruz as var. lemmonii Trel., having longer petioles (1–2 cm) and ovate leaves of 12 × 6 cm. Valencia-A. (2004) does not recognise this variety.

Threatened in the wild by habitat loss for coffee plantations, Quercus germana seems to be established in North American gardens, and is offered by both retail and wholesale nurseries. Its handsome large blue-green leaves flush bronze or reddish, and are densely pubescent in their early stages. Being a white oak, it will probably only thrive in areas with hot summers. At Yucca Do Nursery, Hempstead, Texas, for example, it has survived to –15 ºC (Yucca Do 2008), but in cooler situations it is less successful. Michael Heathcoat Amory notes that in Devon it is often cut back by frost; similarly, a specimen at Thenford House was cut to the ground in the 2005– 2006 winter. (Its response was a flush of shoots in a most amazing beetroot-red!) At the Hillier Gardens the species has consistently failed (A. Coombes, pers. comm. 2006). The only positive record of it in the United Kingdom comes from Tregrehan, where Tom Hudson (pers. comm. 2006) reports that it seems to have no hardiness problems. The tree at the JC Raulston Arboretum was 3.3 m tall, 12 cm dbh in 2006, but has lost its top, and the crown is rather bushy with some twig dieback.