06/24/2026
Our stewardship crew paused beside a patch of ferns at Sawkill Bend a few weeks ago. With the help of Barbara and Anne Hallowell’s classic pocket field guide, we identified Hay-Scented Ferns and several species of Wood Ferns. The real excitement, however, came when we looked closer.
Through a jeweler’s loupe and a macro lens, we discovered the remarkable diversity of sori on the undersides of the fronds. A sorus (plural: sori) is the small structure that forms on a fertile fern. Some are long and curved, others rounded or tightly clustered, and they can appear in different positions on each pinnule (the small leaf-like divisions of a frond).
Each sorus holds clusters of sporangia, the tiny cases that contain spores. Inside each sporangium are the spores themselves. When conditions are right—often in late summer—the sporangia split open and release their spores into the air. Each spore is a microscopic, single-celled structure that can remain dormant until it lands in the right environment. From that single spore, a new fern may eventually grow.
These spore cases are not only intricate and beautiful, they are also reminders that even the smallest details can reveal the astonishing diversity of our local fern community.