The sensitive fern (Onoclea sensitiveus) gets its name from the fact that it withers at the first frost. It can be found almost anywhere, as long as there is moisture. You have probably already seen it, perhaps along the edge of a ditch.
Medium-sized (80 cm), this fern grows in dense colonies. Its light green foliage has a distinctive, roughly triangular shape, divided only once and edged with rounded teeth.
This fern is considered the oldest fern on Earth! Its appearance has remained virtually unchanged for over 60 million years. It is one of the few modern ferns known from fossils.
When you come across it, take the time to observe the delicate veins (its leaves) that run along the blade, the upper part of its stem. In most ferns, the tips of the veins remain free, but in the sensitive fern (Onoclea sensitiveis), the tips meet like the meshes of a net, which is unusual for ferns. However, do not taste it; it is known to be toxic to humans!
Source: Sensitive Fern – Regional Committee for Cliff Protection (parcdesfalaises.ca)
