Limestone outcrops are rare in this part of British Columbia. There is a vein that runs north-south exposed on either side of Vavenby (apparently running at least as far south as Kamloops, too). This forms a nice set of gentle cliffs on
either side of the highway, with relatively easy access. This is the only place in the area to look for a number of species of vascular plants, lichens and probably fungi in general.

A few notable species:

Dermatocarpon atrogranulosum — one of only a few locations this occurs
Solorina saccata — a strict calciphilous species
Collema spp. — most species of Collema are calciphiles