Plant of the Week – February 16th 2026 – Chinese Bramble (Rubus tricor) – Botany in Scotland

Here is another introduced species that has increased rapidly in the last 20 years. It’s a creeping bramble coming from the forests and thickets in the Chinese provinces of Sichuan and Yunnan. It was ‘discovered’ there by the French missionary, explorer and botanist Père Jean-Marie Delavay (1834 – 1895). He collected plants avidly, sending 200,000 herbarium specimens to the Paris Museum of Natural History. However, whilst in China he contracted bubonic plague. He struggled on, came home to recover, but went back to Yunnan despite his continuing illness and continued working for several years until he died there in 1895.

The plant spreads and forms a dense carpet, suppressing other species but, from the viewpoint of parkland managers, it conveniently covers the ground and reduces the need for weeding. Image: Chris Jeffree.

The plant was named Rubus tricolor by Wilhelm Olbers Focke  (1834-1922) the German medical doctor and botanist from Bremen, who toiled for many years to make sense of brambles, and published on Rubus over a long period (1877-1914). It is not clear why the specific name tricolor was chosen (possibly a reference to the French flag, as he obtained his herbarium material from Paris?).

The bristles on the stem and underside of the leaves are especially evident in the young shoots. Image: Chris Jeffree.

Rubus tricolor was first cultivated in Britain in 1909 and was present in the wild (in Derbyshire) in 1976. Unlike the brambles we know, it belongs to the subgenus Dalibardastrum, which has 11 species in China. The ‘true’ brambles of our British hedgerows are in the subgenus Rubus and consist of many microspecies that produce seeds without a sexual process (‘apomixis’). We may write Rubus fruticosus agg. to denote this aggregation of microspecies, as only a few experts can identify plants to the level of microspecies (there are around 350 microspecies in the British Isles but fewer in Scotland – see Angus Hannah’s book Brambles of Scotland,published last year).

The upper leaf surface is without hairs and glossy, and the leaves overlap to provide good ground cover. Soil erosion is probably reduced. Image: Chris Jeffree.

Rubus tricolor is a creeping evergreen shrub, with arching stems. It may not always be ‘evergreen’ as its leaves are shed in harsh winters. The plant itself is however very hardy and survives any cold winters (in China it is found at high elevations – 1800 to 3600 metres). When the shoot tips touch the soil, they form roots and in this way the plant can advance 1 to 2 metres per year. When the stems sprawl and overlap they intertwine and thus a dense mat is formed. There are also rhizomes which form strong aerial shoots.

The stems have numerous yellow-brown bristles, quite unlike the thorns of British brambles – there are bristles also on petioles and the underside of the veins.

View of flowers from above. There are five white petals, each one 7–9 mm long, Image: CHris Jeffree.

So far, its life cycle has not been explored very much. I could find very little first-hand research about R. tricolor on Google Scholar, and the entry in the Flora of China says nothing about the floral biology or ecology. According to internet sources, the flowers are hermaphrodite (i.e. male and female parts being present on the same flower) but cross pollination is required to form seeds (in contrast to British brambles that are nearly all apomictic). Like other brambles, the whitish flowers attract large flying insects. The fruits are red and look like small raspberries but are more globose and softer. Perhaps good to eat if you can find them, but flowering and fruiting is much more limited than in our own brambles. It isn’t clear whether this is also the case in China. We need help from our Chinese friends to find out more.

It is presumed that the fruits are eaten by birds and thus dispersed in the same way as those of raspberries and ‘true’ brambles.

Rare example of a fruit. Image reproduced from https://www.inaturalist.org/taxa/450241-Rubus-tricolor, image by by hattheant, covered by –Creative Commons Licence – NonCommercial 4.0 International.

In Britain R. tricolor is planted as ‘ground cover’ to supress weeds in parklands and to deter vandals around supermarkets and industrial areas. I first spotted it at the University of Edinburgh at West Mains Road next to the James Clerk Maxwell building. This one is clearly a deliberate planting, but it also occurs in the wild state, for example alongside the Water of Leith. Angus Hannah mentions its occurrence along the west shores of Loch Lomond. In our Urban Flora project, we have records of it from many sites over Scotland, where it has been found by paths, cycle-tracks, cemeteries, deciduous woods and by rivers.

Rubus tricolor in Britain and Ireland, showing an increased distribution since the year 2000. From BSBI/Maps.

It is also a favourite of several proponents of forest gardening, a movement akin to agroforestry that harks back to former times when humans simply foraged for their food in the woods. The many advantages of R. tricolor in this context include weed suppression, tolerance of many soil types, low maintenance, edible fruits, pest resistance, protects soil from erosion, doesn’t have sharp prickles, easy to propagate by cuttings, resistant to deer, comes back after fire.

Of course, these characteristics also make it a potential invasive species, liable to overwhelm habitats and lead to a decline in the diversity of woodland floras. Gioria et al. (2023) ask the question Why Are Invasive Plants Successful? I am sure that this species has many of the attributes they mention of a successful invader.  Looking at the data from BSBI/Maps we see how it has spread from the south in a very short time. Since 2020 it has consolidated its position in England and Wales and become a common urban species in Scotland, especially in the Central Belt. It is not yet considered as an invasive alien and therefore not prohibited under the Schedule 9 of the Wildlife and Countryside Act 1981, but perhaps it ought to be. The trouble is, plants are usually recognised as being invasive too late, and therefore the law is not always effective.

World distribution according to Plants of the World Online. Green shows the native distribution, purple the introduced area.

Globally, it hasn’t spread very much. According to Plants of the World Online it is only found in SW China and Britain. Their map is slightly outdated – it is also in Belgium and USA.

Ecologists have generally ‘turned their backs’ on the genus Rubus, a point well made by Hannah (2025), probably because of the difficulty of identification. In the case of R. tricolor there is no such difficulty, but still there is almost no research. We need to know more about its reproductive biology and its life cycle. It has few pests and diseases in Britain, so it is more likely to spread. It may turn out to be a serious threat to woodland biodiversity.

References consulted

Edees ES and Newton A (1988) Brambles of the British Isles. Ray Society, london.

Hannah A (2025) Brambles of Scotland. BSBI Handbook 25.

Margherita Gioria, Philip E. Hulme, David M. Richardson, Petr Pyšek. 2023. Why Are Invasive Plants Successful?. Annual Review Plant Biology. 74:635-670. https://doi.org/10.1146/annurev-arplant-070522-071021 (open access).

Wignall, Veronica R., et al. “Thug life: bramble (Rubus fruticosus L. agg.) is a valuable foraging resource for honeybees and diverse flower‐visiting insects.” Insect Conservation and Diversity 13.6 (2020): 543-557.

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Internet sources

All about forest gardens:

https://www.appropedia.org/Forest_gardens

Collection of photographs from John Norton:

https://www.jnecology.uk/rubus/rubus-study.html

Useful information on an Australian site

https://inaturalist.ala.org.au/taxa/450241-Rubus-tricolor

Foraging

https://atomicshrimp.com/post/2009/07/25/Chinese-Bramble

©John Grace