Does anyone do any Guerrilla Gardening?

[Methe]

I've just been for a walk and littered my neighbourhood with aquilegia seeds from the plants in my garden - not people's gardens but the verges and any other unadorned or neglected space. I'm also planning to 'adopt' a verge in my street to plant some flowers as I've run out of space in the garden.

has anyone else done anything like this? I wonder how long it'd take to notice a difference if I just threw all my collected seeds about the place.

There's a big difference between evolution and man made extinction though. Evolution is genetic changes that usually occur over millennia. Not moving a species to a new environment where it has no natural competition. The species has not "evolved" in any way. You've just put it in a place where it has free reign. This can and does have disastrous effects - the best examples are on remote islands like Hawaii and New Zealand where bird populations in particular have suffered due to the introduction of rats and mongooses. Or here, where red squirrels have been virtually wiped out by the introduction of greys.

When you bring in a non-native species you can't always predict what effect it will have on native flora and fauna. So many garden plants that we think of as pretty are actually pretty rubbish for our native insects. The dandelions that you describe, whilst not "pretty" are probably more beneficial to local wildlife than buddleia- they're good for bees, for example. The buddleia on the otherhand, whilst acting as a nectar source for adult butterflies, doesn't support any butterfly caterpillars (which are pretty fussy about what they eat). When the buddleia turns into a thicket and displaces a field of native plants, you're losing the food source for the caterpillars. So in the long run you actually end up with less butterflies. And what about the other insects, the beetles, flies etc that those native plants used to support? They may have been food for the local bat population etc etc. What you see (pretty plant with butterflies) doesn't even begin to tell the story of what's happening on an ecological level. It's why I dropped ecology at uni- too many complex food webs

That's why sometimes guerrilla gardening scares me- who can predict the impact of spreading new species to the natural environment (not talking neglected flower beds here, obvs)? I can't- can you? They may do no harm at all, but you just can't predict that. Buddleia, knotweed and ponticum were once harmless garden plants as well.

Agree regarding the reintroduction of lynx though, that sounds a bit bonkers unless it's to curb the local deer population.

But 'Bolshy* how can a 'natural bird' be stopped from flying over a country and dropping it's poo there? With seeds in it? Surely that's how a lot of 'invasive plants' arrive? Don't the native insects etc. change their habits to go with the flow?

Some evolve to use new plants and trees, like birds now are happy to nest in non native pines. I know that because we've got plenty in our garden, birds and pines

But that's not evolution. Unless genetic mutations have led to the birds nesting in your trees then it is not evolution. What is more likely is that the birds already had an intrinsically broad definition of where they could nest. This might not apply to all birds however eg some birds might be programmed to only use leaves of a certain shape or size to build their nests and if those leaves disappear they lose the ability to build their nests and hence also disappear. What you're talking about is not evolution, it's using your existing skills to adapt to a new environment. Some animals/birds can do this (foxes!) some very much cannot (giant pandas). For the animals that cannot it often means extinction from that habitat.

Lots of insects cannot "go with the flow"- that's why so many beetles and butterflies are under threat. They have evolved to only utilise a small number of food sources, and once they go, so do the butterflies and insects. Other species move in instead which may be ok or it may be very bad. A classic example of this is what happened when the cod was overfished in Newfoundland leading to an unexpected explosion of jellyfish. What you are suggesting is that, if an organism can't survive in the environment as we decide it should be, then it should die out. This is true but pretty harsh! Should we stop attempting to save rare plants and animals then?

And no, not all invasive species are spread by birds (and even if they are, it doesn't mean you should help them!). JK is spread by cuttings and roots being dumped where they shouldn't and HB shoots it's seeds a remarkable distance.

Sorry, that was a bit long- this stuff was once upon a time bread and butter to me so I'm quite enjoying a good discussion about it