Here's a tweet I just found from, of all places, the town where I live! This was posted in April and here I am in September, so the trail is a little cold, but the tweet includes @BostonParksDept. Maybe the Parks Department was looking for suggestions from surrounding towns? Maybe @LeeToma just thought the Parks Dept would be interested. I will investigate.
There's also this follow-up tweet/photo, supposedly with detail of the sign. I don't know how much more detail there is, but the signs are slightly larger:
