Acer fenzelianum Handel-Mazzetti

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Credits

Dan Crowley (2020)

Recommended citation
Crowley, D. (2020), 'Acer fenzelianum ' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/acer/acer-fenzelianum/). Accessed 2024-03-18.

Genus

  • Acer
  • Sect. Palmata, Ser. Sinensia

Common Names

  • Fenzel's Maple

Synonyms

  • Acer tonkinense subsp. fenzelianum (Handel-Mazzetti) A. E. Murray

Other taxa in genus

Glossary

glabrous
Lacking hairs smooth. glabrescent Becoming hairless.
ovary
Lowest part of the carpel containing the ovules; later developing into the fruit.
pubescence
Hairiness.
pubescent
Covered in hairs.
subspecies
(subsp.) Taxonomic rank for a group of organisms showing the principal characters of a species but with significant definable morphological differentiation. A subspecies occurs in populations that can occupy a distinct geographical range or habitat.
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.
tomentum
Dense layer of soft hairs. tomentose With tomentum.
type specimen
A herbarium specimen cited in a taxonomic account to define a particular species or other taxon.

Credits

Dan Crowley (2020)

Recommended citation
Crowley, D. (2020), 'Acer fenzelianum ' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/acer/acer-fenzelianum/). Accessed 2024-03-18.

A deciduous tree to 20 m. Bark grey to dark grey. Branchlets slender, lenticillate, persistently pubescent. Leaves chartaceous to subcoriaceous, ovate in outline, 8–10 × 10–14 cm, base rounded to cuneate, unlobed to shallowly 3-lobed, lobes ovate, apically acuminate, margins entire to remotely toothed, upper surface bright green, lower surface glossy green, glabrous except for tomentose along veins and along axils, sometimes persisting only in axils; petiole 2–3 cm long, red to green, tomentose. Inflorescence, terminal, corymbose. Samaras 1–1.2 cm long, wings spreading obtusely. Nutlets convex. Fruiting in September (China) (Xu et al. 2008).

Distribution  China Southern Yunnan Vietnam

Habitat Forests and valleys between 1100 and 1700 m asl.

USDA Hardiness Zone 9-10

RHS Hardiness Rating H3

Conservation status Vulnerable (VU)

Rare in cultivation, as in the wild, Acer fenzelianum appears to be represented in cultivation only by one collection, that of Dan Hinkley, under DJHV 06173, collected in 2006 from Seo My Ty in the Hoan Lien Mountains of northern Vietnam, where it was growing with another maple, A. pictum, as well as various Magnolia species and members of the Fagaceae (D. Hinkley, pers. comm. 2018). Since 2006, the area in which this collection was made has unfortunately been denuded of much of its woody flora due to deforestation and though some taxa are regenerating, neither species was found there in 2018 (pers. obs. 2018). DJHV 06173 came to be circulated under A. tonkinense subsp. liquidambarifolium, a synonym of A. tonkinense, and, as of spring 2020, is listed as available as such at Crûg Farm Plants (2020). It is also being grown at the Elisabeth C. Miller Botanical Garden, Seattle, inside the alpine house, where it has reached c. 2.5 m tall and may soon be moved outside (D. Justice, pers. comm. 2020). While the limits of its hardiness are somewhat untested, and though seemingly tender, a plant of A. pictum grown from seed collected at the same Seo My Ty locality (DJHV 06144) has proved hardy at Westonbirt Arboretum, Gloucestershire (pers. obs. 2020).

It is reasonably assumed that the species is named after G. Fenzel, whose collection, Fenzel 44, collected in Sapa, northern Vietnam, represents its type specimen. However, some taxa bearing this epithet, for example Cyperus fenzelianus, are named for an E. Fenzl (1808–1879), an Austrian botanist and former head of the botany department at the Natural History Museum, Vienna. Thus, reference to Fenzl in relation to the naming of Acer fenzelianum in van Gelderen et al. (1994) is considered to be an error.

Morphologically Acer fenzelianum appears closest to A. tonkinense. This is perhaps unsurprising, given the confusion in the naming of the aforementioned collection, while Murray (1969) had treated A. fenzelianum as a subspecies of A. tonkinense. However, the two species are easily split by the abundant, grey to yellowish pubescence on the petioles, branchlets and inflorescences of A. fenzelianum, which in A. tonkinense, aside from the pubescent disk and ovary, are glabrous. Fang (1939) notes that this tomentum may persist for four years.