Non Natives

[oldclaypaws]

The question of non native species is an intriguing and complex one which merits discussion.

Are they a threat, or do others represent great opportunities? Should we aim for 'all native' trees, or be more open minded, trying other foreign species which may be resistant to climate change and disease and have superior qualities to some of the familiar ones we use.

If I was a fuel producer with no consideration for wildlife, wanting a quick growing tree which had no health issues, produced great coppiced fuel that burns superbly and splits well, and replaces my existing threatened Ash, I'd have no hesistation in going for Eucalyptus. Our one tree in our garden grows like stink, I planted it about ten years ago 4ft high and it grew to about 40 ft and 15 inches across in 8 years. Chopped it down, 2 years later its back to 12 feet ! Burns superbly with a blue flame, almost like gas. I reckon if you had 1/2 acre of them, you could heat an average sized home.

Like butterfies? Why not plant a few buddleia? Lots of colour, seems to thrive in the UK.

Even the hated Rhodos, if controlled, might be an interesting choice for fuel, they seem to like our climate and put on a fine show of colour in the spring.

We also have an Alianthus in the garden, looks like an Ash. Grows rapidly, seeds well, apparently great firewood, nice graceful tree. Allegedly invasive, but can't say I've seen it spreading in the wild.

Isn't it a bit purist to think only our 30 or so native trees are the only ones you should plant? We already make use of many which have fitted in well, like sweet Chestnut, Apple, and a host of decorative trees. The colour offered by red oak or red maple might be welcome show in the autumn in an amenity woodland, and our climate is set to change to that of France, so shouldn't we try to have trees that might be better suited?

Our history has been one of actively looking for new plants to try and use, many of them are now familiar 'staples', like the potato, fruit trees, many of our herbs and vegetables, even rabbits and edible snails. (What did the Romans ever do for us?) Some bring challenges, others have been a great success.

If an introduced species out-competes and replaces a native, isn't that just evolution? After all, we did just that to Neanderthals, and nobody seems to be complaining about that one.......

[Zathras]

I think it comes down to the ecosystem balance.

If a introduced species is damaging the an ecosystem, such as when there is a lack of natural predators to keep numbers down or disease carriers or crowding out of diversification going on - then it should be controlled or limited where possible. Good example would be Japanese Knot Weed.

But where introduced species have found a balance with the native ecosystem, then I think we should think it a new paradigm and consider it to all intent and purposes - native.

After all, the ecosystem has been managed by humans for so long now it is difficult to see any of it as truly natural. But I think we all have a good idea of what a healthy ecosystem is and honour bound to stop anything unbalancing it by too much.

[smojo]

It's all just part of evolution isn't it? Things change naturally anyway but I guess the big problems have been caused by man who has kind of "forced" evolution by planting foreign species or bringing non-native animals into countries without knowing how they might be tipping the eco balance. In natural evolution, climates and natural predators might have prevented certain plants or animals from surviving but we have disturbed that balance so much now haven't we. EG the explosion of deer populations wouldn't have happened if we hadn't killed off their predators like wolves and boar. I think it's OK to introduce foreign plants and animals as long as there are some controls and plenty of research done.

Another example of man tipping the balance is due to air travel. Small life forms like insects and bacteria can so easily move from country to country now through this. To some extent I feel we have passed the point of no return on such things because of our multi-cultural networking though travel etc.

[Zathras]

I would say it has nothing to do with evolution directly, whether by naural selection or artificial selection.

But does have an indirect association because there are natural extinction disasters and artificial extinction disasters - which were talking about here when we introduce non-native species by human hand to an ecosystem not able to handle it or destroy a key species unsettling the balance.

Of course our human race is regarded as the most recent major extinction disaster to hit the earth, the last one being a bloody great big rock from outer space...

[Wendelspanswick]

Eucalyptus is a pain to split though, especially when seasoned. We felled a 30yr old specimen and even the hydraulic log splitter on the tractor struggles with it.

[oldclaypaws]

Ours split easily when green (or blue).

Took a while to shake off all the Koalas though.

[boxerman]

This really is such a complicated subject and I'd have to suggest that it's impossible to define 'native species' without first creating artificial boundaries to work from. If you were to take the starting point back to a couple of million years or so then it could easily be argued that very little of what is here now is native. 10,000 years ago we were covered by glaciers and what survived that would have been very basic compared to what we have now. Much of what we rely on for food stuffs such as wheat wouldn't have existed in anything resembling it's current form even 1,000 years ago- it's adapted either naturally or with our help to be what it is today.

Seeds and insects can easily be transported for 1,000's of miles by the winds and migrating birds. Nature brings it's own change in it's own ways. I think the main dangers these days are in the artificially introduced species, carelessly and thoughtlessly introduced by man over the last few hundred years for various reasons such as grey squirrel, American crayfish, mink etc - all of these live successfully, thrive and drive out native species who compete and in some ways it's natural selection although sad to see. Lets be honest here, in a couple of hundred years few people will realise that they aren't native in just the same way that few folk these days would realise that their beloved deer or rabbit were artificially introduced.