I have heard that it is not appropriate to trim/cut off those fronds/runners that grow down underneath the fern itself. Without leaves on them, a stem-like thing that trails under the fern itself. Some are quite delicate and others are clearly stiff stems without leaves. My cat loves to bite those trailing pieces so I would like to trim them so she can't reach them or, at least be less attracted to them. I inherited my fern from my grandmother and my parents were married in front of it in 1937 and it is still going strong and is beautiful. I'd like to have it stay that way. Thanks, Sandra Gillis.
Certified GKH Gardening Expert
Yes, you can trim these off. They are known as stolons or runners, and they are the plant's attempt at finding a new spot to produce baby plants. If they find soil, they will produce leaves. If you don't want the fern to propagate, you can cut them off.