Nyssa sinensis Oliver

Nyssa sinensis is a widespread tree throughout the southern half of China, though perhaps never an abundant one. Like its North American allies, it specialises in wet sites, though it is not adapted to growing in flooded conditions and, in cultivation, it is fully able to exploit free-draining soil. A specimen at the Yorkshire Arboretum planted on free-draining soil at a high point is flourishing and escapes late frost damage that reliably affects specimens growing at the foot of the slope.

Throughout the 20th century, a number of additional Nyssa species from temperate China were described. A 1993 monograph on the genus by J. Wen and T. F. Stuessy (Wen & Stuessy 1993) used physiological features to suggest that the glabrous N. shangszeensis Fang & Soong was distinct, with the small-leaved N. leptophylla Fang & T. P. Chen and N. wenshanensis Fang & Soong seeming more closely allied to the subtropical species N. javanica and N. yunnanensis. In 2012 Wang et al. (Wang et al. 2012) employed phylogenetics to investigate this perceived muddle and demonstrated that these various temperate forms, along with the persistently pubescent N. shweliensis (W.W. Sm.) Airy Shaw, were all part of a continuum of closely allied variants and were best described as a single, widespread and variable species, for which N. sinensis Oliver remains the earliest available name.

The species was noted by Augustine Henry in 1888 and was first introduced to the West in 1901–1902 by Ernest Wilson, collecting for Veitch’s Nursery (Bean 1976), but it languished in obscurity for many decades in a few arboreta; its larger-growing American ally N. sylvatica had reached Britain in the 18th century and was already established as a niche, autumn-colouring specimen tree, while Bean’s own description of N. sinensis as a garden tree is lukewarm at best.

Recently, a better appreciation of this tree’s merits has begun to form. N. sinensis seems more at home in the cool summers of northwest Europe than do the American Tupelos and may even show more brilliant and reliable autumn colours (Exbury Garden 2021); no other Chinese tree outperforms it. High-altitude forms will also be reddish or purplish as their leaves unfold. Its compact stature and often graceful habit help give N. sinensis a place in smaller gardens, and it seldom, if ever, suckers aggressively. It lacks the attractively rugged bark of the American tree, but makes up for this with its more elegant, refined-looking foliage. Nyssa in general are rather anonymous-looking trees in summer leaf, vaguely resembling any number of other genera and providing a challenge – or an opportunity – to tree watchers who are just learning to differentiate the less common forms. Although, in evolutionary terms, N. sinensis is quite close to N. sylvatica, learning to recognise one will probably not help you to recognise the other: with its typically longer, darker and more leathery leaves, N. sinensis in summer may even be assumed to be evergreen and to be ‘some kind of laurel’ – a guess (completely wrong) that the drumstick-like arrangement of its tiny greeny white flowers might help to endorse. Although not showy, these flowers are quietly attractive, and, in the United Kingdom, the display of small dark blue fruits that follows in autumn is the best the genus has to offer (Exbury Garden 2021).

N. sinensis may not prove very long-lived in cultivation, but there are currently thriving younger trees in a variety of bigger gardens across England, Wales and Ireland. Examples of 10 m at Llanover Park in South Wales and 9 m at Mount Usher in the east of Ireland show the species’ ability to cope with rich and slightly alkaline conditions, even though the genus as a whole is considered calcifuge, and an acidic soil will certainly enhance the autumn colour. Chinese Tupelo seems equally happy at Pine Lodge Pinetum in the Atlantic climate of Cornwall and at East Bergholt Place in Suffolk’s dry summers, where trees 9 m tall are growing exceptionally well. The northernmost example recorded for the Tree Register (2021) is a rather stunted and bushy one, 5 m tall, in the Old Parsonage, a part of Manchester’s Fletcher Moss Botanical Gardens, but continued experiments may well reveal a capacity to cope with cooler, more northerly conditions.

Some mature specimens have formed rounded crowns on several stems; these may have been distributed by the Hillier Nurseries through the third quarter of the 20th century and include the champion at the Sir Harold Hillier Gardens, with a spread of 13.7 m by 2011 (Tree Register 2021). Others, such as the tree by the old drive gates at Nymans in West Sussex and examples at Queenswood Country Park in Herefordshire and at Chevithorne Barton in Devon, carry a straight trunk high into the crown and are plants of outstanding grace.

Among the local variants that were historically understood as separate species, Nyssa leptophylla, with its rather shorter and flimsier leaves, was introduced to the West by seed from Hunan distributed by China’s Qingpu Paradise Horticultural Company in 1998 (QPH 98.149). Plants from this seed have grown well at Tregrehan Gardens in Cornwall, where the autumn colour is red, and at Wynkcoombe Arboretum in West Sussex (obtained via Pan-Global Plants), where in deeper shade it turns pale yellow. The variant is now sold – always, presumably, from the QPH seed – by nurseries across the United Kingdom, Ireland and France. Available from Crûg Farm Nursery, FMWJ 13122 was collected in the Hoàng Liên Son Mountains of northern Vietnam and was originally suspected to be N. shweliensis. The leaves unfold purple, and vigorous young plants retain a purplish cast through summer (Caerhays 2020).

In the United States, N. sinensis has understandably failed to compete as an ornamental with the native N. sylvatica, though some forms are hardy enough to survive in the Arnold Arboretum of Harvard University in coastal Massachusetts, and the Chinese species as a whole seems less vulnerable to leaf spot (Dirr 2009). Experiments by the late Dr Frank Santamour showed that these two species hybridise readily (Dirr 2009).

In the United Kingdom, several selections of N. sinensis have been sold for the reliability of their autumn colours. iN addition to those described below N. sinensis ‘Nymans Form’, sold until 2017 (Royal Horticultural Society 2021), may have derived from the tree at Nymans with excellent habit, while ‘Savill Form’, sold until 2013 (Royal Horticultural Society 2021), was presumably selected from one of two relatively bushy examples in the wildflower meadow at the Savill Garden in Windsor Great Park; ‘Savill Sparkler’ in the National Collection at Exbury may represent the same clone. Chris Sanders (pers. comm. 2021) has however noted that the cultivars do not necessarily outshine unselected specimens of this excellent species.