The Alton Grange Association (AGA) is an incorporated, non-profit volunteer group who manages the Grange property in partnership with the Ministry of Natural Resources (MNR). The Grange property consists of 350 acres and is situated adjacent to the village of Alton in the Town of Caledon. It is bounded by Hwy 136 on the west and north; by Beechgrove Sideroad on the south and by Porterfield Rd on the east. The property contains wetlands and two rivers, Shaw’s Creek and the Credit, flow south and converge on the property. Much of the higher land was reforested with pines in the 1930’s, but there are considerable areas of natural hardwood and mixed forest, plus meadows and open floodplain.
The property was purchased by MNR in 1974 and managed as an Integrated Resource Management Area but with budget cuts, MNR needed help to manage the property. A 'Partnership Agreement' was signed with AGA to manage the property, one of only two such agreements in the province. To date the group has helped build a boardwalk, clear trails, collect garbage and plant trees. They have also hosted educational days on the property in partnership with MNR.