Not A Trail!!
Well... It is on the Map. It has a Number. Maybe, long ago it was a real spur trail.
Now, it is the continuation of a nice, wide gravel road. The road winds up from Ruidoso to access the heavy logging activity that prevailed on top of Grindstone Mesa, the debris of which still dominates the Ridgetop.
This route leads you down off the top of GrindStone Mesa and across over to the boundary of the National Forest and the Mescalero Indian Reservation. Since you are not supposed to access the reservation area without permission, this road walk might serve better as the end of an out and back mountain bike ride along the road.
It would be nice to think it could be an augment to hiking or biking the Grindstone Mesa Loop Trail (91A), but unfortunately, that trail does not exist either. There are some old logging roads that could afford access out and across the Mesa, but you'd have to find your own way.
At this time they are surveying and plotting a new loop route in addition to a new route up and down the Grindstone Trail (91). It could be years before those routes are fully established. For now, consider experiencing this area without the benefit of established trails. Bike the road sections. Hike the off trail expanses of the Mesa. Cut down and off to Sawmill Canyon, off trail, and enjoy the various old logging roads to be found in the lower levels of the canyons.
Do not bother looking for this Spur Trail... no one else does. The roadway cut spoiled the area for any sense of a trail environment.
Check out the Triplogs.