It's Skull Canyon On the Map!
Of the many access routes up to the Crest Trail, this one may be the more difficult to locate.
The route starts off of Forest Road 108 (Tanbark Canyon) across private land. You are right next to a house. Of course, given it is the only house on the west side of the road, it makes it easy to find.
The Topo Map shows the trail as Skull Canyon Trail, and it also shows the trial passing up into Tanbark Canyon. Tanbark Canyon is really the main drainage along Forest Road 108.
A nice aspect of the trail: it is one of the steeper routes up... if you are looking for a harder effort, this might be the trail for you.
On a practical basis, this trail will be combined with one or three of the other area trails to compose a fun day. You might decide to head up to Nogal Peak, looping from the top of Skull Canyon along the Crest Trail (#25), over to Nogal Peak Trail (#26), then perhaps back down Tanbark Canyon along Forest Road 108? If you do that loop, consider heading up from the Crest Trail to the ridge holding the peak trail... there is no reason to loop all the way down and around... enjoy the little cutoff off trail!
Skull Springs Trail could also combine with any of the variety of lower trails rising out of the Bonito Creek drainage: Turkey Canyon Trail (#40), Argentina Canyon Trail (#39), Big Bonito Canyon Trail (#36)... or many others. The potentials are boundless.
Pick your route, plan your day... go enjoy!
Check out the Triplog.
This hike is listed as One-Way.
When hiking several trails on a single "hike", log it with a generic name that describes the hike. Then link the trails traveled, check out the example.