How to Prune leathery polypody?
Remove any dying fronds as necessary.

leathery polypody · Polypodium scouleri
Also known as: coast polypody
Grow in a reasonably fertile, humus-rich, moist but well-drained soil in partial to full shade. Shelter from cold, drying winds and protect with a dry winter mulch such as straw or lift and overwinter in a cool greenhouse.
Remove any dying fronds as necessary.