Sycamore good or bad?

[Paul mabbott]

Clearly a plantation so you wouldn't expect very much!
But one of the most apparently 'sterile' natural woodlands in the country are the yew forests of Sussex and surrounds. Yew (Taxus) is, of course, a native species and, where it takes hold, it seems to create a deathly dark and silent wood ..... but actually there is quite a lot of insect life in there - you just need time (and a lamp) to find it!

Going to the general topic of coniferous woodland - they are different, obviously, from deciduous woods but you shouldn't assume that they are 'sterile' - sure there'll be very few flowering plants, butterflies &c but if you take the time to look around in the litter, you'll probably find quite a lot of large ground beetles and, in the canopy, various other beetles ....

I'd be interested to know if there's anything 'specific' for cedar woods in UK?

Originally Posted by arvens is

Deviating slightly off topic but theres woodland near me which the pre-dominant species is some sort of cedar(wester red I think). Walking through it, it is dark and lifeless bar one or two species of Fungi where the ground has more or less been 'sterilised' by the needles - if thats the right word for them.

Mark

[RobSutton]

Originally Posted by Paul mabbott

Going to the general topic of coniferous woodland - they are different, obviously, from deciduous woods but you shouldn't assume that they are 'sterile' - sure there'll be very few flowering plants, butterflies &c but if you take the time to look around in the litter, you'll probably find quite a lot of large ground beetles and, in the canopy, various other beetles ....

I'd add in Red Squirrel, Siskin and Crossbill which all depend on conifer plantations in non-Scotland UK for any chance of success.

[svenrufus]

Originally Posted by Paul mabbott

The recent 'British Wildlife' summary by Alexander et al has been quoted elsewhere.
Species diversity, of course, is usually interpreted as a product of biomass (individual numbers) and species number. There have been plenty of examples in the entomological literature of interesting, even rare, species living on sycamore. I'm not sure what you mean by 'UK specialists'. Nor am I sure how there can be a 'negative influence' on biodiversity except in the case of unproductive trees such as plane.

I think your definition of invasion is different from mine. You describe sycamore filling gaps in woods - not growing into woods at the expense of trees already there. I think that a lot of the "problem" is purely in the mind of the beholder - if you become obsessed with removing it then you will only see that problem recurring. You, for instance, are talking about seedlings &c - what happens if you leave them? My bet is that most would die, the occasional one will grow to maturity and have no effect on the overall balance of the woodland. In effect, we shall never know what the effects of this putative invasion are because no one lets it proceed! I restate my observation that I have never seen evidence of sycamore invasion in any reasonably sized, undisturbed, semi-natural wood.

I'm going to make this my last post on this thread for fear of the risk of being labelled an obsessive, which I'm not (I hope). First off, I just want to say how enjoyable it is to have a debate about sycamore where my views are challenged by statements a hell of a lot more substantive than 'they look nice'. Good stuff. Also, thanks to you Paul, and to Rob Sutton, for pointing me in the direction of very interesting articles on the subject. I have learnt a lot from those.

That said, I remain to be fully convinced. I accept that I didn't appreciate the range of species that sycamore hosts, and I am grudgingly yielding on the idea of the biodiversity that they support.

As far as the native/non-native debate, I have read various articles now suggesting that it might be native, particulalry in the NW, but I don't find them compelling, and there is at least as much (more?) research with very good evidence about it's recent arrival, albeit disagreement about exactly when.

A few comments in reply to the quoted posting.
Diversity - the way I was using this is related not just to the tree specifically, but also the contribution that a tree makes in the community of other trees it lives alongside. My understanding (being re-appraised in light of the articles I have since read) is that while there is a large biomass, even with a decent species count, the contribution sycamore makes to biodiversity is relatively low compared to what a native species would have added to the area, as sycamore did not host species not otherwise supported by 'native' trees. By the term 'UK specific' I clumsily tried to express 'endemic specialists dependant on sycamore'.

Regarding sycamore invasion of woodlands - I stand by what I said, although you may be right to say that it is only a problem if I choose to see it that way, which I do. I disagree with the idea that there is such a thing as an 'undisturbed semi-natural woodland' anywhere in the UK, as the dynamics of woodland constantly open up new spaces, disturbance to the canopy, disturbance to light falling on the woodland floor, etc. Distubance is a vital process, and sycamores do exploit this at the expense of other trees. Near where I live, Bursted Woods was a beech woodland before the '87 storms, at least as far back as 1780. OK, '87 was extreme disturbance, but Bursted is now pre-dominantly sycamore secondary woodland. A bit further up the road at Stanmer Woods, much less impact from the storm, but with a few mature sycamores in the Beech canopy, the understorey is now dominated by sycamore saplings of all sizes, and no, if left in place they don't die. They grow tall, (very skinny) and reach into the canopy, waiting for disturbance (a la '87?)to allow them to take over the space from other species.

It would be interesting to see what would happen if a sycamore wood was left to mature, to see if other species find a place after a while as suggested with the ash/sycamore cycle hypothesis, but I won't be around to argue about the results, so where's the fun in that? Meanwhile, whatever the merits of the sycamore for whatever invertebrate species it supports, I will follow my instinct (prejudice?) and looking at the evidence from woods I know, and others I visit and survey.

On balance, I'm still for removal wherever an option. I am now looking at things with more of an open mind though, and my position may change with time.

Thanks again to all for an interesting debate.

[Paul mabbott]

Pleased to see you keeping an open mind - I wish more could do that!
A couple of points, briefly: I doubt that we shall ever know the answer to the 'native/not' debate because the arguments tend to get rather circular - the only way we can date the presence of any tree is from pollen analysis - unfortunately we can't tell the difference between the Acer pollens!
Anyway, my view is that it doesn't matter - organisms that got over before the Channel opened are rather a random selection ...

Originally Posted by svenrufus

..............
As far as the native/non-native debate, I have read various articles now suggesting that it might be native, particulalry in the NW, but I don't find them compelling, and there is at least as much (more?) research with very good evidence about it's recent arrival, albeit disagreement about exactly when.

......................

It would be interesting to see what would happen if a sycamore wood was left to mature, to see if other species find a place after a while as suggested with the ash/sycamore cycle hypothesis, but I won't be around to argue about the results, so where's the fun in that? Meanwhile, whatever the merits of the sycamore for whatever invertebrate species it supports, I will follow my instinct (prejudice?) and looking at the evidence from woods I know, and others I visit and survey.
On balance, I'm still for removal wherever an option. I am now looking at things with more of an open mind though, and my position may change with time.

It would, indeed be interesting - indeed in northern woods there is no evidence that in the long term sycamore takes over a wood, any more than ash, oak or beech.... but that needs someone to monitor it regularly for a couple of centuries .... I would but ....

Cheers, Paul

[RobSutton]

Originally Posted by Paul mabbott

Pleased to see you keeping an open mind - I wish more could do that!
A couple of points, briefly: I doubt that we shall ever know the answer to the 'native/not' debate because the arguments tend to get rather circular - the only way we can date the presence of any tree is from pollen analysis - unfortunately we can't tell the difference between the Acer pollens!
Anyway, my view is that it doesn't matter - organisms that got over before the Channel opened are rather a random selection ...

It would, indeed be interesting - indeed in northern woods there is no evidence that in the long term sycamore takes over a wood, any more than ash, oak or beech.... but that needs someone to monitor it regularly for a couple of centuries .... I would but ....

Cheers, Paul

I'd agree with Paul's comment about northern woods - I've don't know of any where the sycamore has been more of a problem than ash or beech and probably the worst tree for supressing growth of other species I've seen is holly. I know of a couple of woods where almost the entire ground layer has been lost under holly. The comment I'd make in general terms about conservation management is that all too often in the past it has been reduced to a formula - like sycamore is bad get rid of it or grazing is bad put a fence up. I think every wood is probably different in terms of its species compostion, grazing regime, geology, aspect, history etc and all these need to be taken into account in preparing a management plan. Sometimes stopping grazing or getting rid of sycamore might be best - but not always.

By the way glad I could help with the articles Sven.

[Wild-Woman]

What a sensible and balanced debate. For us 'not in the know' it has been an education and food for thought. Thank you for keeping it civil and friendly. You should all be politicians....Then again stick to wildlife.

Jules

[Buzzy]

Hi ya,

I don't want to set up a sided comment but I have to say I mostly agree with Sven on this topic. I've had plenty of experience with sycamores and they are not good ones. I know how they can rapidly dominate an area and seed everywhere they land for what seems like miles around. It would be sad to see any species persecuted but I do believe in controlling nature when the balance is tipping towards what appears to be a singular dominant.
Does this make sense ?
I hope we can all use this site to help us have a greater understanding of ourselves within nature, as it is quite often because of our actions that the delicate balance of ecology becomes unbalanced.

We need to be managers of this planet and it's natural life. As we are the only species that can veiw the whole, and see what is happening to it.

Speak to you soon !

[annie0367]

I quite agree that sycamores should be controlled as they are just huge weeds as far as I am concerned.
I have 7 of them in my back garden and it makes controlling them extremely difficult.
I just wish the didn't have TPOs on them.

What am I to do? :-(