Here are some links that FOHP members might find interesting:
This is the 'official' page of the Harold Parker State Forest
A great write-up of Harold Parker's history on the North Shore Nature website.
The Andover Trails Committee is a citizens committee including members of the Conservation Commission, the Appalachian Mountain Club, Andover Village Improvement Society, the Bay Circuit Alliance, The Trustees of Reservations, and just plain folk who appreciate the outdoor recreational opportunities of Andover. It was reactivated in the spring of 1991 to focus on the establishment of the Bay Circuit Trail in Andover.
Friends of North Andover Trails is a not-for-profit, community-based organization dedicated to preserving and supporting North Andover's public trail system.
NEMBA (New England Mountain Bike Association) is a recreational trails advocacy organization who dedicates themselves to taking care of the places that they ride, preserving open space, and educating the mountain bike community about the importance of responsible riding.

This is the website for the Field Pond Watershed Association. Field Pond is one of the largest ponds in Harold Parker (it's on the South side of Harold Parker Road).
Ferns of HPSF, compiled by Don Lubin

Other 'Friends' Organizations:
Massachusetts Forest and Park Friends Network is an independent grassroots organization of volunteer "friends groups" working together to better protect and enhance Massachusetts’ state forests and urban parks. The Department of Conservation and Recreation (DCR) oversees 259 properties in Massachusetts. Currently only about 34 friends groups serve particular forests and parks. Our goal is to see a strong friends group in every forest and park in the Commonwealth.
Friends of Upton State Forest
Friends of the Assabet River National Wildlife Refuge