One very common way to group ferns for identification purposes is by the number of times each frond is divided, or "cut". For more information about this, please see the Fern Glossary page.

Undivided

These are ferns having fronds that are not divided into leaflets. Each frond is a single "leaf" which is not split or "cut" into leaflets.

Hart's Tongue Fern (Asplenium scolopendrium)
Northern Adder's Tongue (Ophioglossum pusillum)
Walking Fern (Asplenium rhizophyllum)

NO CUTS

Once Divided

Each frond is divided into leaflets only once; ie, it is "cut" in only one direction.

Christmas Fern (Polystichum acrostichoides)
Purple-stemmed Cliffbrake (Pellaea atropurpurea)
Slender Cliffbrake (Cryptogramma stelleri)
Smooth Cliffbrake (Pellaea glabella)
Northern Holly Fern (Polystichum lonchitis)
Narrow-leaved Glade Fern (Homalosorus pycnocarpos)
Polypody (Polypodium virginianum)
Sensitive Fern (Onoclea sensibilis)
Smooth Woodsia (Woodsia glabella)
Ebony Spleenwort (Asplenium platyneuron)
Green Spleenwort (Asplenium viride)
Maidenhair Spleenwort (Asplenium trichomanes)

ONE CUT

Twice Divided

Each leaflet is further divided into subleaflets; ie, it is cut in two directions.

Braun's Holly Fern (Polystichum braunii)
Cinnamon Fern (Osmundastrum cinnamomeum)
Crested Shield Fern (Dryopteris cristata)
Goldie's Fern (Dryopteris goldiana)
Long Beech Fern (Phegopteris connectilis)
Male Fern (Dryopteris filix-mas)
Marginal Shield Fern (Dryopteris marginalis)
Marsh Fern (Thelypteris palustris)
Ostrich Fern (Matteuccia struthiopteris)
Royal Fern (Osmunda regalis)
Silvery Glade Fern (Deparia acrostichoides)
Virginia Chain Fern (Woodwardia virginica)

TWO CUTS

Thrice Divided

Each leaflet is divided into subleaflets, and each subleaflet is further divided or cut into "sub-subleaflets".

Daisy Leaf Grape Fern (Botrychium matricariifolium)
Bracken (Pteridium aquilinum)
Bulblet Fern (Cystopteris bulbifera)
Fragile Fern (Cystopteris fragilis)
Cut-leaved Grape Fern (Sceptridium dissectum)
Leathery Grape Fern (Sceptridium multifidum)
Lady Fern (Athyrium filix-femina)
Maidenhair Fern (Adiantum pedatum)
Oak Fern (Gymnocarpium dryopteris)
Rattlesnake Fern (Botrypus virginianus)
Robert's Fern (Gymnocarpium robertianum)
Intermediate Wood Fern (Dryopteris intermedia)
Spinulose Wood Fern (Dryopteris carthusiana)

THREE CUTS

Closeup view of a subleaflet that is split into sub-subleaflets, for a thrice-cut frond. This gives the fern a very lacy or frilly look. This is a Spinulose Wood Fern (Dryopteris carthusiana).

	Here's another sequence of photos to illustrate a thrice divided or thrice cut frond. This is the first division or cut, which divides the frond into leaflets or pinnae.
	The second division or cut, which divides each leaflet into subleaflets or pinnules.
	And the third division or cut, which divides each subleaflet into sub-subleaflets or lobes. For more information about this, please see the Fern Glossary page.
	And all three divisions or cuts shown together. For more information about this, please see the Fern Glossary page.

Ferns Learning to ID Ferns Fern Silhouettes Leaf Divisions Glossary