The South Side

This is from the main entrance going west.  There is a small clump of trees before the stone drainage ditch. The first three look like some sort of fruit tree, apple was the most common in the area for years. 

After leaving out in the summer and some online consultation, These three small tress are probably Cherry trees.  The suggestion is Prunus serrulata a variety that has no fruiting. In addition the leaves as of the summer show "cherry shot hole disease".  The holes in the leaves are non-specific, more than one cause but may indicate too high humidity and poor air circulation around the leaves.

one trunk of the group of three Cherry trees

?Cherry shot hole disease

There is a large conifer near the road, there are no obvious cones.  The needles seem to arise from small cups on the twigs and do not roll easily between the fingers so tentatively calling it a fir. Cones would be nice to be more specific. Near the stone drain is a red oak.  A long line of small shrubs stretches along the parking side.  Tentatively these are called Virginia sweet spire a native shrub with white flowers in the spring and summer, colorful leaves in the fall.

East of the white stones are three Fringe trees, a guess from remembering the leaves in the fall.  These are opposite buds, fitting the MADHorse opposite mnemonic by being part of the ash family. Close to the parking lot is another tulip tree . Further west are four Hollies, showing the dioecious nature of the holly.  Two have berries, female, and two do not , probably male.  Toward the parking from the holly  is an unknown alternate leaf bud deciduous tree.  Then there are three pines, probably white pines close to the road. In front of the pines are three more of the semi-unknown trees with peeling bark, possible hornbeam.  On the other side of the fence are three large maples.

More homework.  Watch the fruit trees for early buds, the fringe trees for male or female type. Watch the first leaves or fruit to identify the unknowns.