Cornus controversa Hemsl.

One of two dogwoods with non-opposite leaves, Cornus controversa is commonly encountered as a well-proportioned spreading tree with rather dense foliage borne on horizontal branches. Mature specimens make airy trees of elegant habit, with upright boughs and slender branches that bear their leaves in a graceful billows. A tall tree in bloom is a magnificent sight. In younger trees the tabular branching habit is often pronounced, particularly on trees grown as a single stem, producing the striking tiered effect that has earned the tree one of its vernacular names, ‘Wedding Cake Tree’, a name that is particularly apt in the case of the pale cultivar ‘Variegata’.

Cornus controversa belongs with its North American counterpart C. alternifolia in subgenus Mesomora, an early-diverging lineage of the blue-fruited dogwoods that is sister to the generally shrubby subgen. Thelycrania. These two species depart from the opposite phyllotaxy that is otherwise constant throughout Cornus, the leaves often described as alternate, though the disposition of the buds is not arranged in a regular alternating pattern, but varies from irregularly sub-opposite to an apparently pseudo-whorled condition produced by the shortening of internodes towards the tips of stems – see the discussion under Cornus alternifolia.

In its ability to form a tall tree, Cornus controversa is distinct from its shrubbier American counterpart, and in the case of established trees there is little danger of mistaking the two species, though younger specimens can be much harder to distinguish, particularly from a distance and when encouraged into their ‘wedding cake’ forms. Actually, the main risk of confusion (surprisingly) is with an opposite-leaved species from a different subgenus, namely Cornus macrophylla, which greatly resembles C. controversa in general appearance and habit. From a distance, the two are easily confused, and indeed, the names Cornus macrophylla and its synonym C. brachypoda were in the past often misapplied to C. controversa (Bean 1909), rendering it all but impossible to uncover the date of the species’ first introduction. Plants listed in late-ninetenth-century British catalogues as C. brachypoda argentea marginata or C. brachypoda variegata are obviously referrable to forms of C. controversa, but the identity of material listed simply as C. brachypoda before about 1909 can be much harder to ascertain.

Distributed throughout East Asia and the Himalaya, Cornus controversa was not described until 1909 by Hemsley (Hemsley 1909; Bean 1909), though it had by then already been in cultivation for several decades under different names. Veitch is said to been growing Cornus controversa at the Coombe Wood Nursery in 1880 (Arnold Arboretum 1920) – this would appear to be the ‘Cornus brachypoda’ described by James Veitch in Some Lesser-Known Japan Trees and Shrubs as ‘a handsome dogwood, some 15 feet high, clearly distinct from [C. macrophylla]’ but its identity as yet undetermined; curiously Veitch did not mention the unusual phyllotaxy, though his remark that ‘a variegated form is unusually attractive’ would seem to settle the question of the plant’s identity (Veitch 1903).

The origin of this early cultivated material is uncertain, though the name Cornus brachypoda was often used to refer to plants of Japanese origin, and the simultaneous appearance of variegated forms strongly suggests a cultivated origin (a further argument in favour of Japan, where such garden varieties had been selected for centuries). Wild-sourced Chinese material was not introduced until the first decade of the twentieth century, when E. H. Wilson found the species growing abundantly in western Hubei. WIlson sent seed back to the Arnold Arboretum in 1907 under Wilson 83 (from Patung Hsien at 1000–1300 m) and Wilson 219 and 133 (Changyang Hsien, 1300–1600 m), though this material does not appear to survive at the Arboretum today. George Forrest’s final expedition collected the species from Yunnan, southwest China, in 1930–32 (Forrest 30157), introduced to the United States under PI 99849 (United States Department of Agriculture 1933).

An instructive photograph in Wilson’s archive shows a single-stemmed 18 m tree with a 2 m girth from near Wa-shan at 1100 m (Z-371 – perhaps corresponding to W 1848, collected earlier that year). The close proximity of clear-stemmed neighbouring trees of similar height suggests that the tree had been drawn up under forest conditions before the surrounding area was cleared for cultivation.

Cultivated trees can be free-flowering, though plants raised from wild-collected seed can vary in their performance (J. Grimshaw, pers. comm. 2026). If a standard tree is desired then a leader should be selected early to ensure the formation of a central trunk from which the tiered branch system can develop (Brown & Kirkham 2004). On the other hand, early introductions grown as multistem specimens have produced tall, graceful trees with billowing tiered crowns, as seen in the British champion tree at Forde Abbey, Dorset. Bean (1976) noted that the branching pattern could result in a particularly attractive winter silhouette.

The autumn foliage display is usually discounted, though in some selections, notably ‘June Snow’, the leaves turn attractive shades of orange and red; Bean (1976) partly attributed such autumnal colour to different soil types. Cornus controversa tends to be earlier into leaf than C. alternifolia (risking frost damage to the foliage), but it shows greater tolerance of continental heat than the American species (Cappiello & Shadow 2005). A moist loam is often prescribed, but experience suggests that most reasonable soils will suffice: trees thrive as isolated lawn specimens, an arrangement that particularly shows off the shapely form of ‘Variegata’.

Propagation is by cuttings, layers, or seed. Cultivars are nearly always grafted, ideally onto C. controversa stocks, but in practice sometimes onto shrubby C. alba, C. amomum or C. alternifolia, effectively precluding any possibility of developing a well-formed tree, as well as inviting future trouble with suckering (Gayraud 2013; Junker Nursery 2022).