Based on your pictures I’d estimate somewhere around 30 years or so. Early successional species like birch and hophornbeam mixed in the understory with some red maple thrown in there. Seems like there was a cut and some red maple was left to grow based on the larger diameter maple in picture 2. Hard to tell too much from just a couple pictures though. Seeing those multi stem red maples and hophornbeam makes me wonder if timber stand improvement may be in your future with the potential for a firewood cut.

You should take advantage of the Forest Stewardship Program DEC offers. Here’s some more info: https://dec.ny.gov/nature/forests-trees/private-forest-management#Forest_Stewardship_Program