Focussing on the facts, as you suggest @Penguin68...
There's a small woodland to the north of the large Sainsbury's, known as Dog Kennel Hill Wood and it's fab (I recommend a visit - real haven in the city). The clues it's a woodland include the large number of trees hanging out together in one place. The Woodland Trust recognise this means its woodland(https://www.woodlandtrust.org.uk/visiting-woods/wood/41153/dog-kennel-hill-woodlands/), so do Southwark Council (https://www.southwark.gov.uk/parks-and-open-spaces/parks/other-parks-and-gardens?chapter=5). The good news is that it isn't under any threat.
The Friends of Dog Kennel Hill Wood is the Friends Group for this woodland - and they're taking an interest in what's happening in the adjacent Green Dale Fields (where the current Astroturf is).
There's a separate friends group for Green Dale Fields - The Friends of Green Dale. [www.friendsofgreendale.org.uk