Salmonberry (Rubus spectablis). Appearing in a location near you..

I wish they weren’t all Californian

I live on the Arran ring road, and although it doesn’t really have a name where I live, the Post Office seems to refer to it as Shore road. Perhaps the bit from Brodick School to the Castle should be renamed Invasives Row, or after the prinicpal invader, Salmonberry Boulevard. I use this street name because the plant is a native of West Coast USA from California northwards. When people hear that a plant comes from California they think of sun and warmth, but the North West of the State is foggy, damp and the ideal environment for ferns, mosses and general greenery. It is not suprising then that many of our forest trees hail from this part of the world, such as the Sitka Spruce and Douglas Fir. In the US these damp woodlands are thought of as temperate rainforests, a term that is starting to be applied to the UK’s western woods.

The Salmonberry (Rubus spectabilis) has found a niche here on Arran and it is going for it. I am guessing that at the moment a lot of people don’t know the plant. All I can say is that they soon will and will soon be adding suitable adjectives to its name. This plant is in the same genus as bramble and though it doesn’t have a creeping habit, it has extremely spiny thorns and is troublesome to remove. When or how it came to Arran I am not sure, but it is on the increase and poses a real threat to woodlands, gardens and possibly pasture.The plant grows over head height and consists of a number of stems from a central rootstock. It comes into flower pretty early, from February onwards and often before coming into leaf. The berries appear on the plant in summer and thus offer a bramble type feast before the autumn. Here lies a problem for the control of Salmonberry, as the plant is spread quite commonly by birds, and therefore has a lot of mobility. Who knows where a bird is going to do its business having eaten the berries. Aside from Salmonberry Boulevard, it appears frequently in Whiting Bay and I’ve seen some on the shore in Sannox. If anyone has any reports from further afield I would be happy to receive them.

 Like all non-natives, the Salmonberry takes habitat away from other plants. It appears to be a coloniser of open ground, but it can seed into grassland as well. There does appear to be ground vegetation in some places where it grows, whereas other places it is so dense it precludes all other plants. If you do a search on the internet for UK examples, you won’t find much mention of it as a problem, though in Northern Ireland it is found all over. In Scotland it is present in Orkney and the major infested area has been Corstorphine Hill in Edinburgh. Arran could be set to be its major stronghold, a dubious distinction.Salmonberry is being put forward as a Schedule 9 species, which will mean that it will be an offence to plant it and “let it out” of your garden. However, the problem with invasive species it that we like to bolt the stable door after the horse has bolted, in that people wait to see if a species is a problem and when they realise it’s a problem its already too late. It is not that Salmonberry is invincible, Dawyck Botanic Gardens have been pretty successful in ridding the garden of it. There they used a brush cutter and then sprayed the re-growth with a herbicide, Timbrel. Roundup (glyphosate) is less pungent, but will kill Salmonberry. Unfortunately, it grows so big that you need to cut it back and let it regrow a bit in order to be able to reach all the plants and also prevent spraying everything in sight. Another option is to cut the stems back and paint the stumps with herbicide, but you have to get every stem though to stop resprouting. I have had success with this in the wintertime. The branches are pretty difficult to get rid of as they are bulky and they require a very good fire to burn, so shredding is perhaps the best option. Though I hate to be pessimistic about invasives, I don’t hold out much hope for beating Salmonberry on Arran. Wind dispersed seeds have to spread incrementally, but this one could appear anywhere and form enticing food to leapfrog to a new area. It would however be nice for others to learn from this “mistake” and not plant it elsewhere and control it as soon as it appears.