just place the uvseams at the right corners and noone will see with the first look. the other maps like moss/grass - masks and the ambient occulution shadows (which are all produced independent to the seams) will also help to lead the eye away from the seams.
yeh, superroe is right, the stone, grass and moss are photosourced. I made screenfilling textures of them and then painted the mask of them on the rock. for the moss mask I began with the information of the ambient occulution shadows which resulted from the highpoly. specular comes from the diffuse. normal is baked from…