There is a group of evolutionarily ancient ferns referred to as “Grape Ferns.” Although they are true ferns, they are only distantly related to the ferns growing today. They derive their common name from the resemblance of their (spore-producing) sporangia to a bunch of tiny grapes. Grape Ferns have two blades. One is sterile and does the photosynthesizing; the other is fertile and bears the grape-like sporangia.
Different species of Grape Fern mature at different times during the summer. Leathery Grape Fern (B. multifidum; Sceptridium multifidum) is the largest of the Grape Ferns. Its triangular, sterile blade is very leathery and fleshy. If the fern is growing in full sun, the stalk of the sterile blade is usually quite short, and the branching, fertile blade rises above it. The spores on the fertile blade mature in late summer or early fall.