The Northern Mewuk say:
In the beginning the world was rock. Every year the rains came and fell on the rock and washed off a little; this made earth. By and by plants grew on the earth and their leaves fell and made more earth. Then pine trees grew and their needles and cones fell every year and with the other leaves and bark made more earth and covered more of the rock.
If you look closely at the ground in the woods you will see how the top is leaves and bark and pine needles and cones, and how a little below the top these are matted together, and a little deeper are rotting and breaking up into earth. This is the way the world grew--and it is growing still.