About Dryopteris affinis (Lowe) Fraser-Jenk.
Dryopteris affinis is a fern species that is nearly evergreen. It produces light green fronds that are 60 to 160 cm (24 to 63 in) long, with a moderately stiff, hard texture. The rachis at the base of each frond is densely covered in yellow-brown scales called ramenta. Fronds of this species are bipinnate; pinnae grow up to 8 to 18 cm (3 to 7 in) long, and the pinnules are broadly rectangular, with the most toothed margins located close to the pinna tip. A blackish spot is present at the base of each pinna, where it connects to the rachis. Individual fronds live for approximately 1.5 years, and remain attached to the rhizome after they wither. Dryopteris affinis is closely related to Dryopteris filix-mas. It can be distinguished from that species by its typically more robust growth habit, generally more evergreen fronds, more densely scaly frond stems, and more rectangular (less tapered and lobed) pinnae and pinnules. It is one of the larger ferns native to Europe. Older specimens develop a dense, nearly tree fern-like base that reaches 20 to 30 cm (8 to 12 in) high and 30 to 40 cm (12 to 16 in) broad. Many cultivars and varieties of Dryopteris affinis have been selected for garden cultivation. The following cultivars have gained the Royal Horticultural Society's Award of Garden Merit: D. affinis 'Polydactyla Mapplebeck', 'Crispa Gracilis', 'Cristata', and 'Cristata Angustata'.
