"The entire forest should be wired for cell service as a public safety issue." - I would like to see cell coverage on the roadways, in campgrounds and other places where people gather in numbers; other than that, I think a cell phone is just the wrong tool to go venturing into the back country. Especially to do any climbing, which increases the odds of a mishap.
My hope is that people who go beyond the common areas will get and learn to use a SPOT beacon, or some other satellite-connected emergency beacon. I think that's a better tool for the task.
I know the world wants cell phones to be all and do all, but they ain't there yet, by a long stretch. They may never be.
I saw one of those "bison silhouette" cell towers in Colorado, traveling north from Denver. It looks like an art work, unless you glance sideways just as you pass its nose, and see that it's a flat plate of some kind, with the antenna blades on one side of the plate. Great stuff.
Drive north on Carnelian Ave., I think that's Rancho Cucamonga, and turn right onto the 210 Freeway onramp. There's a gazebo/shade structure looking thing there, appears for all the world to be a building. But I'm 99 1/2% sure it's a cell tower. Many are disguised as buildings these days, not just as odd trees. Although one of my former bosses was literally leaning with his hand on the rough trunk of this giant 'palm tree', and was genuinely surprised when we told him it was a cell tower. And I bet most people around here have seen what looks like a water tank labeled "Phelan" just north of Phelan Road, as you drive between Victorville and Phelan. There's another tower that looks like a sign, too.