Free stuff like this doesn`t have to be called bryce only, it is a wavefront object and can be used in almost any 3d program, poser 5 users could use this as bryce materials can mostly be duplicated in the poser 5 material room. If it was in the freestuff as a wavefront object then more people would download it and use it, you could say in the notes that it was specifically made for bryce but will work with other programs with some work.