Mounting Angraeceum leonis on a branch?

[markr]

Sphagnum is used when mounting orchids as a way of maintaining a little more moisture at the roots between waterings in environments that aren't humid enough (such as the typical living room). In my experience, anything below 70% RH long term is not enough for exposed Angraecoid roots, which are quite thin and dry out easily. First sign of trouble is that the orange (or green for some) root tips stop growing.

If you regularly spray the roots twice a day or so, you could probably get away with bare roots in a dry room. If you are growing it in a terrarium, greenhouse, plant window, or other humid enclosed space, the sphagnum isn't necessary - directly attaching the plant to a branch is fine and probably best.