Saxifragaceae
Thanks to Wildflowers of Garland Ranch by Michael Mitchell and Rod M. Yeager, I knew both hill star and woodland star occur here. It's been a very handy go-to guide for local plants. Three years ago I photographed the square-calyxed L. heterophyllum, and I've been on the search for this v-shaped L. affine ever since. Note the pretty red stem.
ps 04/22/14 - I discovered there are other Lithophragma found in our area. I just noticed the 3-lobed petals shown above have notches, whereas the green one I photographed at Pinnacles does not. I don't know if that's a common variation of L. affine. There is a possibility this is a smallflower woodland star (Lithophragma parviflorum var. parviflorum), but I don't know the difference.
ps 04/22/14 - I discovered there are other Lithophragma found in our area. I just noticed the 3-lobed petals shown above have notches, whereas the green one I photographed at Pinnacles does not. I don't know if that's a common variation of L. affine. There is a possibility this is a smallflower woodland star (Lithophragma parviflorum var. parviflorum), but I don't know the difference.