Although there is a move by some local people and voluntary groups to have Warren Farm referred to as Warren Farm Nature Reserve I would mention that it is not a designated nature reserve under the relevant legislation and the name is therefore misleading.
This is not to say that it doesn't have wildlife value or shouldn't be managed for wildlife. But it's a fact that this, along with the vast majority of nature conservation sites in Ealing, isn't a designated nature reserve.
This note includes comments from anonymous users which should be independently verified.
What does the signage say? It's OSM's job to map whatever we see, not to arbitrate on the legality of it. Though it's often reasonable to add an alt_name that's different to the signage if it helps people find a location through another name.
It might be worth asking on https://lists.openstreetmap.org/listinfo/talk-gb - that way, more locally-based mappers may see it.
Note that we have two closely related notes here. See:
I started a thread earlier today at https://forum.openstreetmap.org/viewtopic.php?pid=815322#p815322 . No replies there as yet, but I have invited Milhouse and Hanwellweather who have previous edits there.
I replied to the forum post now, but it's awaiting moderation before anyone can see it!
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