An interrupted fern (Osmunda claytonia) is a deciduous fern native to North America. It usually grows in moist, wooded areas under part to full shade.
The interrupted fern gets its name from small fruiting bodies that form between the larger leaf blades, which are called pinnae. These brown leaflets seem to interrupt the green leaves on the larger fronds. The interrupted fern usually grows to between 2 and 3 feet tall, but with constant moisture it can reach 5 feet in height. It does best in damp, acidic soils but can adapt to almost any garden soil as long as it is under shade.