Crow’s Nest: Native fern diversity

Now that summer is ending I am finally getting around to compiling data that was gathered at the beginning of the season. On June 9 the Philadelphia Botanical Club and the Delaware Valley Fern and Wildflower Society visited Crow’s Nest with a plan to document the flora of a small part of the preserve. They will make several field trips over the next couple years to further inventory the diversity of plants that grow here. Below: the New York fern, Thelypteris noveboracensis. Top: Northern lady fern, Athyrium filix-femina var. angustum.

We found fifteen species of fern here that day, a few more than I realized we had:

• Bracken fern – Pteridium aquilinum
• Sensitive fern – Onoclea sensibilis
• New York fern – Thelypteris noveboracensis
• Lady fern – Athyrium filix-femina var. angustum
• Spinulose Wood fern – Dryopteris carthusiana
• Evergreen Wood fern – Dryopteris intermedia
• Christmas fern – Polystichum acrostichoides
• Marginal Wood fern – Dryopteris marginalis
• Marsh fern – Thelypteris palustris
• Silvery Glade fern – Deparia acrostichoides
• Hayscented fern- Dennstaedtia punctilobula
• Cinnamon fern – Osmunda cinnamomea
• Interrupted fern – Osmunda claytoniana
• Royal fern – Osmunda regalis
• Ebony spleenwort – Asplenium platyneuron

Here is a view of the sori of the marginal wood fern, Dryopteris marginalis:

And those of the silvery spleenwort (silvery glade fern) Deparia acrostichoides:

A photo of royal fern, Osmunda regalis, winding through other vegetation:

A view of marsh fern, Thelypteris palustris:

And sensitive fern, Onoclea sensibilis:

Posted by Daniel Barringer on August 24, 2012.