An important point for attaching a member of the fern family is to cut off old leaves of ferns, such as Bolbitis and Microsorum, as much as possible before attaching them to driftwood. Old mature leaves do not easily adapt to a new environment and algae tend to grow on them. The tip of a young growing leaf of Microsorum is transparent. You should keep mainly these young leaves and cut off old ones. In the case of Bolbitis, you can cut off most of the large leaves. In an extreme case it is quite fine to attach only the rhizomes to driftwood. Doing so allows the ferns to develop clean new leaves that are adapted to the new aquarium environment.
http://www.aquatic-gardeners.org/Articles/driftwood/
http://www.aquatic-gardeners.org/Articles/driftwood/