@Lizzie27 I have considered buying it, or part of it, but I think it is too big and would be too much of a liability for us, as you say. Still it's nice to daydream about extending the garden or turning it into a little park!
I've worked out that the problem plant is Symphoricarpos albus, or Snowberry. It's really horrible for spreading and not a native plant at all. I might need to do some more research on invasive plants and see if I can get any help to get rid of it.
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