Nothofagus cunninghamii (Hook.) Ørst.

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Credits

Owen Johnson (2020)

Recommended citation
'Nothofagus cunninghamii' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/nothofagus/nothofagus-cunninghamii/). Accessed 2021-01-18.

Common Names

  • Myrtle Beech

Synonyms

  • Fagus cunninghamii Hook.
  • Lophozonia cunninghamii (Hook.) Heenan & Smissen

A tree to 55 m tall (Wikipedia 2020), sometimes with a long trunk to 2 m thick, but shrubby or even prostrate at high altitudes. Bark grey, horizontally banded with pale lenticels then becoming closely scaly and divided by deeper, vertical, often orange-based fissures. Twigs red-brown, downy; very slender (c. 1 mm thick); buds yellowish green, slender, c. 3 mm long. Leaves evergreen, mostly triangular with a truncate base but sometimes broadly ovate or rhombic or almost orbicular, the tip broadly pointed, 8-18 mm × 6-15 mm and smallest on old trees; leaf-margins (except at the base) bluntly and irregularly single-toothed; both surfaces glabrous but the margin sometimes ciliate; lamina glossy rich green, sometimes sprinkled with pale dots, flushing yellow then coppery or bright red in sun, and turning red or yellow before the leaf falls (after c. 2 years); petiole downy, very short. Male flowers solitary, with an irregularly 6-lobed perianth. Cupule c. 6 mm long, dividing into 4 narrow valves, covered with short decurved bristly lamellae, each of which is terminated by a globular gland which hardens as the fruit ripens; nutlets 3, the centre one flattened. (Nothofagus 2007–2008); (Bean 1976).

Distribution  Australia Victoria: in mountain forests at the southern extremity of the Australian Alps. Tasmania: throughout the island but less common in the drier Midlands and east coast.

Habitat Mountain forests to 1300 m asl; forming pure stands on rich soils in Tasmania and otherwise mixed with other evergreen trees.

USDA Hardiness Zone 8

RHS Hardiness Rating H4

Conservation status Vulnerable (VU)

With its tiny, toothed leaves held densely in elegant, evergreen tiers, the predominantly Tasmanian Nothofagus cunninghamii quite closely resembles the New Zealand N. menziesii and is one of remarkably few examples of similarity between the floras of these islands. (A few plant species have been able to spread from island to island relatively recently; in the case of these southern beeches, which are relics of ancient Gondwanaland forests, little genetic divergence has occurred during the long period through which the Australian and New Zealand populations have remained isolated.) The wild population is now considered Vulnerable (Baldwin, Barstow & Rivers 2018) due to dieback observed in wild stands during recent dry conditions (particularly in Victoria) and to losses from Myrtle Wilt infection (Chalara australis), which is specific to this tree.

Nothofagus cunninghamii has been grown in Britain since around 1860 (Bean 1976) and is seen almost exactly as often as N. menziesii (73 records on the Tree Register versus 75), but mature examples are confined slightly more markedly to areas with adequate summer rainfall, and which are not too cold in winter. Most of the biggest are in Ireland, but the largest of all is in the grounds of the Stonefield Castle Hotel in south-west Argyll, Scotland, in a sheltered but very maritime microclimate. In 2012 it was 24 m tall with a trunk 116 cm thick, at 60 cm below the even fork of two stems (Tree Register 2020). With its huge luxuriant crown this specimen is beginning to approach the grandeur of ancient trees in native forests, but the narrow fork - characteristic of many older plantings - may limit this specimen’s long-term stability; there is not yet any evidence to suggest the species will be very long-lived in northern hemisphere cultivation and none of today’s trees seem likely to be more than a century old.

Among younger trees which might suggest the species’ limits in Britain, a slender specimen planted in 1970 over Cotswold limestone at the Batsford Arboretum in Gloucestershire was 13 m tall in 2014, although seedlings show yellowing in a soil pH of 7.5 or higher (Nothofagus 2007–2008). In 2009 another good young tree, then 11 m tall, grew on the Rossway estate in Hertfordshire, on acidic soil over chalk, in one of the warmest and driest parts of England. A 1974 planting had grown to 9 m by 2019 in the shelter of Ray Wood at Castle Howard in North Yorkshire, where 17°C of frost was recorded in 2010 (John Grimshaw, pers. comm.). When young and on a good, well-watered soil, N. cunninghamii can grow faster than its neat habit and tiny, bonsai-like leaves might suggest: a 2003 accession (from ETAZ 14) was 13.6 m tall after 15 seasons’ growth within Coates Wood at Wakehurst Place in West Sussex (Tree Register 2020). The species’ happiness across a range of growing conditions is in marked contrast to the performance to date of the only other indigenous Tasmanian Nothofagus, the high-altitude specialist N. gunnii.

As is the case with many Nothofagus species, the statistics held for trees growing in the UK and Ireland by The Tree Register provides almost the only evidence for this tree’s cultivation outside its natural range. It is perhaps too tender and too drought-sensitive to be a worthwhile prospect in continental Europe, or even in the western United States. Ødum et al. report that the species survives as a shrub on the Faeroe Islands but is regularly damaged by winter cold (Ødum, Hansen & Rasmussen 1989). In New Zealand, a specimen grows in the Huatoki Walkway garden in New Plymouth (Church 2013).