The Bike Fairy paid you a visit. As for trail, you can calculate it here:

Bicycle Trail Calculator | yojimg.net

Angle finders can be had for cheap at the local hardware store. If memory serves, mid/high 30s (mm) trail and less is considered 'low'. Tough to eyeball it in the picture due to shadow/fork turned away from the camera, but you might be at the high-end of low trail at least (i.e. into the 40s+). Now that I've said that I'll be proven wrong. I believe low trail is more valuable for front loads than gravel grinding in particular. Low trail may make that bike a bit more nervous/twitchy than ideal for its intended buyer. Either way, enjoy.