The Hoh's forest floor is densely carpeted with sword ferns and oxalis (wood sorrel), plants adapted to the very low light beneath the closed old-growth canopy. Some, like oxalis, can fold their leaves to avoid damage from rare direct sunlight. This lush, shade-tolerant understory is a defining layer of the temperate rainforest's structure.
Look down low for a change, at the floor of this forest. It's carpeted in sword ferns, big arching fronds shoulder-high in places, and in among them a clover-like ground cover called oxalis, wood sorrel, blanketing everything in heart-shaped green. There's so little direct sun down here that these plants have learned to live on the dim, watery light that filters through the canopy, and some of them fold their leaves shut when a stray sunbeam gets too strong. The giants get all the attention, but the real lushness of a rainforest is down at your boots.
Photo: Ron Clausen · CC BY-SA 4.0
