To mount, or not to mount, that is the question: Whether ‘tis nobler in the mind to suffer the slings and arrows of outrageous fortune…
Sorry, got a bit carried away there. The question is not Shakespearean but concerns whether you should buy mounted or unmounted staghorn ferns.
If you are planning to put your staghorn on a wall, divider, trellis or column, then having it mounted on a board is usually the best solution as the mount, and hence the fern, will be able to be attached to a hook or nail and will be flat against its supporting structure. As the staghorn gets bigger, it may well attach itself to the wall etc. If not, then the mounting board can be attached to a larger board.
On the other hand, a staghorn which is going to be attached to a tree is usually unmounted. It can be simply folded around a tree (or a bough) of an appropriate width and tied on with a rope, wire, fishing line or straightened coat hanger, depending on what is available. Pantyhose, glue and nails can also be used, separately or in combination.
The photos below show a Stagosaurus staghorn which has been tied to a swamp box tree in bushland in a rural housing community south west of Brisbane. At the time that the photos were taken, the staghorn had been on the tree for about 12 months.
The rear view shows the straightened plastic covered wire coat hanger which attaches the staghorn to the tree. This was not visible in the frontal view as basal fronds had grown over it.
This rear view shows the wire unclipped. The staghorn has attached itself firmly to the tree and does not need the support of the wire, which has been removed in the final photo.