Quercus look Kotschy

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Credits

Allen Coombes & Roderick Cameron (2021)

Recommended citation
Coombes, A. & Cameron, R. (2021), 'Quercus look' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/quercus/quercus-look/). Accessed 2024-03-29.

Genus

  • Quercus
  • Subgen. Cerris, Sect. Cerris

Common Names

  • Hermon Oak

Synonyms

  • Quercus aegilops subsp. look (Kotschy) A. Camus
  • Quercus brantii subsp. look (Kotschy) Mouterde [comb. invalid.]

Other taxa in genus

Glossary

Critically Endangered
IUCN Red List conservation category: ‘facing an extremely high risk of extinction in the wild’.
IUCN
World Conservation Union (formerly the International Union for the Conservation of Nature).
acorn
Fruit of Quercus; a single-seeded nut set in a woody cupule.
apex
(pl. apices) Tip. apical At the apex.
calcareous
Relating to lime- or chalk-rich soils or water.
cupule
Cup-shaped structure formed from coalescent bracts. Typical of Fagaceae and Nothofagaceae. May be dehiscent (as in e.g. Castanea) or indehiscent (as in e.g. Quercus).
dbh
Diameter (of trunk) at breast height. Breast height is defined as 4.5 feet (1.37 m) above the ground.
hybrid
Plant originating from the cross-fertilisation of genetically distinct individuals (e.g. two species or two subspecies).
included
(botanical) Contained within another part or organ.
monograph
Taxonomic account of a single genus or family.
pubescent
Covered in hairs.
reflexed
Folded backwards.
synonym
(syn.) (botanical) An alternative or former name for a taxon usually considered to be invalid (often given in brackets). Synonyms arise when a taxon has been described more than once (the prior name usually being the one accepted as correct) or if an article of the International Code of Botanical Nomenclature has been contravened requiring the publishing of a new name. Developments in taxonomic thought may be reflected in an increasing list of synonyms as generic or specific concepts change over time.
taxon
(pl. taxa) Group of organisms sharing the same taxonomic rank (family genus species infraspecific variety).

Credits

Allen Coombes & Roderick Cameron (2021)

Recommended citation
Coombes, A. & Cameron, R. (2021), 'Quercus look' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/quercus/quercus-look/). Accessed 2024-03-29.

Small deciduous tree, to 10–15 m, sometimes a shrub 1–3 m. Bark blackish, fissured on mature trees, trunk often short and twisted. Branchlets reddish brown, glabrescent at season end; buds brown, conical, glabrescent, with stipules up to 1 cm long. Leaf blades thin but coriaceous, oblong, narrowly oval-lanceolate, widest at the middle or lower third, 6–15 cm long × 3.5–8 cm wide, base and apex attenuate, margin usually wavy, with 3–9 pairs of small lobes, mucronate, aristate and unequal; leaves emerge densely covered in stellate pubescence, upper surface becoming dark green and glabrous, lower surface paler and with sparse pubescence, 6–10 pairs of veins branching frequently before reaching the margin; petiole short, 1–1.5 cm. Acorn cup hemispherical, 2–2.5 cm tall × 2.5–3.5 cm wide, enclosing half to two thirds of the nut, scales coriaceous, glabrous, broadly oval, ending in an acute, brown apex, upper scales reflexed, the rest straight; acorn barrel-shaped or turbinate, apex typically truncate, depressed by around 2 mm, nut 2–3 cm long × 2–2.3 cm wide, grey pubescence persisting around remains of the style, sessile, borne singly or in pairs. (le Hardÿ de Beaulieu & Lamant 2010).

Distribution  Israel North LebanonSyria

Habitat Montane forests between 1500 and 1900 m, in association with Cedrus libani, Sorbus spp. and Acer hyrcanum subsp. tauricola, on western slopes of Mount Barouk (Lebanon), and associated with Quercus infectoria, Acer monspessulanum subsp. microphyllum, Styrax officinalis, Pyrus syriaca and Crataegus azarolus in Mount Hermon and on the eastern slopes of Mount Barouk.

USDA Hardiness Zone 7

RHS Hardiness Rating H6

Conservation status Endangered (EN)

Though previously Quercus look was considered a naturally occurring hybrid between Q. libani and Q. ithaburensis (Hedge & Yaltirik 1994) and sometimes treated as a synonym of Q. ithaburensis (Govaerts & Frodin 1998), Michael Avishai (2017) suggested it was a valid taxon, based on the observation of trees on Mount Hermon. Molecular work by Simeone et al. (2018) confirmed the uniqueness of Q. look and found it was closely related to Q. cerris, not Q. libani, as earlier supposed. Quercus look is the southernmost representative of the mountainous deciduous oaks in the Middle East. It is an important element of the open deciduous mountain forest between 1500 m and 1900 m on Mount Hermon, Mount Lebanon, and the Anti-Lebanon Mountains, growing on west- and north-facing slopes and in shady ravines, on hard, calcareous, well-drained soils. Trees are seldom found isolated or grouped in small clusters, or in open forests, but rather occur in the understory level in cedar forest stands, codominant with other broad-leaved trees or in pure formations. It appears to be tolerant to high temperature amplitude and to moderate drought. In aspect it is intermediate between Q. brantii and Q. ithaburensis, from which it can be distinguished by less pubescent leaf undersides, acorns more enclosed by their cups, and shorter, less reflexed cupule scales. Lobing is often irregular, which is not the case with Q. brantii (le Hardÿ de Beaulieu & Lamant 2010). The truncated apex of the acorn, which is sometimes slightly concave, also sets this species apart (Fragman-Sapir 2019).

The area of occupancy for this species is estimated to be a mere 200 km2, severely fragmented into 14 subpopulations. It is threatened by climate change and grazing, and currently listed as Endangered by IUCN (Stephan 2018).

Most of the trees currently held in collections originate from seed distributed by Michael Avishai in the early 2000s. Following the Six-Day War in 1967, nature reserves were established on Mount Hermon and oaks that had been overlogged and overgrazed in the past were allowed to recover and eventually fruit again (Avishai 2016). It was these plants that prompted Avishai to reexamine the taxon and establish that they corresponded to the species described by Kotschy and collected at the same location. Acorns harvested here were distributed to collectors and trees now grow in Arboretum de la Bergerette, Arboretum de Pouyouleix, and Arboretum de Passadou in France, Iturraran Botanical Graden in Spain, Arboretum Kruchten in Germany, Sir Harold Hillier Gardens in England, and Aiken Citywide Arboretum, South Carolina and The Bartlett Tree Research Laboratories and Arboretum, North Carolina, in the United States. A slow growing species, it has nevertheless proven hardy and come through tough winters (down to –21°C) unscathed (Avishai 2017). An older generation of specimens originates from a tree of unknown origin attributable to this taxon, which has grown in the Dijon Botanic Garden since the mid-1960s (F. Picard, pers. comm. 2008). It was the parent of a tree growing at Arboretum Waasland, Belgium, which in turn was the source of a specimen at the Arboretum Günther Diamant, Duisburg, Germany (E. Jablonski, pers. comm. 2006) and another at Thenford House – at 16.5 m × 0.4 cm dbh, the UK and Ireland champion according to Tree Register (2021). As the tree at Waasland came as seed from Dijon, it is possibly a hybrid with Q. cerris. Plants distributed from Waasland, such as the tree at Thenford, are also likely to be this hybrid. This may explain their untypical fast growth of over 1m per year. According to le Hardÿ de Beaulieu & Lamant (2010), specimens of Q. look in cultivation aside from those introduced by Michael Avishai – appear to be incorrectly identified. Trees grown from seed collected in Israel are at the Jerusalem Botanical Gardens (The Jerusalem Botanical Gardens 2021).

Kotschy described the species in 1860, from specimens he had collected on the eastern slopes of Mount Hermon in 1855. The description was included in his magnificent monograph Die Eichen Europas und des Orients (1858–1862). The specific epithet is based on the local name for this oak amongst the inhabitants of Rachaiya, a village just to the north of Mount Hermon. Given the fact that the name was transliterated by German-speaking Kotschy, the pronunciation is probably something like ‘lohk’.