amantell20's picture

Cotoneaster?

Observed: 10th June 2012 By: amantell20amantell20’s reputation in Plantsamantell20’s reputation in Plants
DSC06075
Description:

Growing on brownfield site calcareous grassland. Can it be identified to a species? I think this is an invasive non-native species?

Identifications
Species interactions

No interactions present.

Species with which Cotoneaster interacts

Comments

corylus's picture

Looks like C.horizontalis

the Herringbone Cotoneaster which is the common garden sp.Yes, they & other species are invading & threatening native flora.

Hazel Trevan

amantell20's picture

Cotoneaster

Thanks Hazel - now I know what it is I will have a chat to the Council to see what they can do about it!

Adam

AlanS's picture

Introduced species are rarely "invasive"

"now I know what it is I will have a chat to the Council to see what they can do about it!"

So what will they do? Come along and spray the area?

There are numerous Cotoneaster species in Britain. Very, very locally a few can be somewhat invasive and potentially a threat on limestone cliffs, but they are not generally a problem or a threat to native vegetation.

Set against this the fact that some are now rare in cultivation and established wild populations may be of conservation interest, not to mention their interest to many botanists.

Quite possibly this is indeed C. horizontalis, which is frequently bird-sown on walls and wasteground, and not important one way or another. However, the principle of trying to exterminate any non-native species is one I find quite offensive.

I am not saying some species are not invasive, though scientific investigation of impact on our native flora does not always support casual assumptions. Some species are definitely big problems - Crassula helmsii for example, or the gene-flow from Spanish and Hybrid Bluebells into native populations. But casually established bird-sown Cotoneasters? No.

amantell20's picture

Alan, thanks for your

Alan, thanks for your thoughts. While my phrasing may have been unfortunate you are reading far too much into my very brief note! Having spent 20 years working for the EA in water resources management including advising govt, industry and the environmental lobby I am not so naive to suppose that we should (or indeed could!) remove non-native species unless there were a very good reason to do so.

In this instance however, the Cotoneaster is relatively abundant, it is freely seeding, there are many juvenile plants and it is located in an exposed former limestone quarry with extensive cliff habitat. There are also 2 BAP species present in this area to my knowledge which I believe could be impacted not only by the Cotoneaster but also general scrub invasion. Hence my concerns.

I am happy to acknowledge that I am not an expert, and my next step would be to speak to the Council who have adopted this area of land to see what, if anything, they can do to ensure the site stays in good condition. I also realise they will have many other priorities for their resources, but if this is a problem that can be nipped in the bud early (if you pardon the pun), then perhaps it should be.

I would welcome any advice you may be able to offer, as it sounds to me like you have some knowledge of this kind of situation? But I would also advise you not to jump to conclusions too quickly after reading very brief comments!

AlanS's picture

Ah , not your usual brownfield site ...

"In this instance however, the Cotoneaster is relatively abundant, it is freely seeding, there are many juvenile plants and it is located in an exposed former limestone quarry with extensive cliff habitat. There are also 2 BAP species present in this area to my knowledge which I believe could be impacted not only by the Cotoneaster but also general scrub invasion. Hence my concerns. "

In this case I entirely agree that action is justified. Indeed C. horizontalis is a species that can have a considerable shading effect with its flat, spreading branches and relatively opaque leaves - not good for seedlings of native species, or indeed for any mosses and lichens on the cliffs. Quite different from my mental picture of a bird-sown colonist on derelict land.

I should also have looked at the location. Not a good area for C. horizontalis to be building up populations!

Yes, I was jumping to conclusions here and apologise. I do find attitudes to introductions or presumed introductions to be sometimes problematic if not alarming, but I understand that this is not an example!

Alan

amantell20's picture

Thanks for your note Alan. I

Thanks for your note Alan. I did incidentally have a quick look at your excellent web site. Having done some work on Lichens (Peltigera) at Bristol Uni, albeit a long time ago, it was quite inspiring. Perhaps this is an area I should look at again!

Adam