Have you ever looked on the underside of a fern frond and seen strange little brown bumps? Those are the sites of reproductive spores called “sori” (the singular being “sorus”), which is very different than the much more recent evolution of seeds in plants. Well, Onoclea sensibilis take things even further. Instead of having its spores on its normal fronds, it has two separate types of fronds – ones that just hold reproductive spores, and ones that are green and feed the plant via photosynthesis. Onoclea sensibilis is called the “sensitive fern” because it’s non-fertile fronds quickly fade when touched by the first frost. However, its brown fertile fronds persist (photo here) and are quite interesting to look at in winter. The specimen pictured here was collected in the Nipissing District of Ontario by staff member Ben Stormes in 2018.