Quercus × leana Nutt.

Quercus × leana was described by Thomas Nuttall in 1842, who named it after Thomas G. Lea, who discovered the tree in question near Cincinnati, Ohio, around 1830. Nuttall pointed out a similarity to Q. × heterophylla but concluded that it was either a distinct species or ‘another strange hybrid.’ He quoted Lea, who believed it to be a hybrid, most likely between Q. imbricaria and Q. velutina or Q. coccinea. Nuttall was sceptical about the possibility of oaks hybridising spontaneously and so dismissed Lea’s accurate insight, publishing instead as a species. It was later encountered elsewhere, as solitary individuals in widely separated locations over the southeastern US, according to Sargent (1895). Palmer (1948) reported it had been brought into cultivation in botanic gardens both in the US and in Europe. Le Hardÿ de Beaulieu & Lamant (2010) praise its rapid growth and attractive display of spring and autumn colours. Bean (1914) expressed doubt as to whether all the trees given this name were of the same origin, although it was certain that Q. imbricaria was one of the parents. He reported seeing trees in the Arnold Arboretum with leaves 7.5 to 15 cm wide. In his opinion, however, it was ‘always a vigorous, handsome oak.’

It is found in several gardens in the UK, the largest at Royal Botanic Gardens, Kew, obtained from the Van Volxem nursery in Brussels and planted in 1873. It measured 19.5 m × 58 cm in 1964, 18 m × 66 cm in 1978 (apparently having lost its top in the interim) and 20 m × 89 cm in 2022, seemingly growing thicker rather than taller in recent decades. A larger tree used to grow at Hollycombe, West Sussex, measuring 20 m × 92 cm in 2007, but has since been lost. The tallest tree in the UK is at Tregrehan, Cornwall, planted in 1892, reaching 23 m on a slender trunk 77 cm in diameter in 2024 (Bean 1976; Clarke 1988; The Tree Register 2025).

It has grown significantly larger in European gardens, presumably preferring the climate there. At Waux-Hall, Bergen, Belgium, a tree boasts a trunk 162 cm in diameter (2015) and used to soar to 36 m, but has since been struck by lightning and lost a significant part of its crown. The current Belgian champion is at Kasteel Van Everberg, Kortenberg, a modest 23 m tall but with a trunk 167 cm in diameter. The tallest Lea’s Oak recorded in Europe, according to Monumental Trees (2025), is in Schlosspark Heltorf, Angermund, Germany, 31 m tall in 2020 with a trunk 140 cm in diameter, but the Beltrees inventory records a tree that measured 32 m × 141 cm in 1996 (Beltrees 2025). A particularly elegant specimen is found at Arboretum Kalmthout (pers. obs. RC 2025), reaching 20.8 m × 82 cm in 2018 (Monumental Trees 2025).

Presumably larger trees can be found in habitat in the US, but the champion tree programs no longer record hybrids. Three spontaneous Q. × leana grow at the Oak Ridge Cemetery in Springfield, Illinois (see photo of one below), among the impressive 57 hybrid oaks at the cemetery, spontaneous and planted, representing 21 different hybrids (Oak Ridge Cemetery Foundation 2025). A notable specimen grows in Central Park, New York, by the Shakespeare Garden. It could plausibly be a spontaneous hybrid and was identified as Lea’s Oak by Chaya and Bernard (2013). The chance similarity of the oak’s name and that of Shakespeare’s King Lear led Cameron (2022) to wonder whether it could be baptised Lear’s Oak, perhaps evoking the mention, in Lear’s diatribe against the storm while out on the heath, of ‘oak-cleaving thunderbolts’, such as the one that topped the champion oak at Waux-Hall (see above).

The name chosen by Nuttall is the adjectival epithet based on the surname of the discoverer, Lea. This presumably was preferred to the option of a substantival epithet, which would have resulted in the awkward Q. × leae.