First, the access roads are mostly excellent if you arrive via FR 48, to FR 4810, to FR 4811, and then FR 2710. The first three roads on that list are paved. The last one is in fine shape, apart from the final quarter mile where it traverses a steep hillside on its way down from a ridge top to the creek bottom. That last bit is narrow enough you don't want to meet another vehicle on it. On the whole, it's all very passenger car friendly. There's a 7 site campground, Bonney Crossing, a hundred yards from the trailhead that is open year round **(see note below) and run by the Forest Service rather than a concessionaire.
The trailhead has a small parking area, good for about 4 cars. It's at 2100 ft. The trail starts out staying close to the creek, in an open dry land forest of mostly pines and oaks for most of the first 4 miles and gains elevation very gradually. On this stretch there are numerous campsites, but all of them are very public to the trail, sited in the narrow strip between the trail and the creek.
I made my camp near the junction with Post Camp Trail, the first trail to join the Badger Creek trail at about the 7.5 mile mark. There was a very large obvious and overused campsite just past this junction, but I chose to track down the Post Camp trail toward the creek (where there is a bridge) and chose a smaller site a minute's walk from the bridge. This is at about 3300 feet elevation.
The next morning I took a quick walk up the trail, maybe a half mile past the next trail junction with the Badger Cutoff trail. The trail up there was a bit rougher, narrower and less maintained, but still entirely passable. This photo shows the worst bit I saw. It was short.
**Note: I should explain that by "open year round" I mean Bonney Crossing campground is ungated and campers are welcome to camp there even when no services are being provided, as for example toilet paper being replenished in the vault toilets. A fee is charged only when those services are in effect - during the summer months.
