Those strange growths erupting from the bases or trunks of redwoods, often resembling molten lava, anthropomorphic shapes or mythological creatures, remain a curiosity to forest hikers and botanists.
There are three kinds of burls. Basal burls, located at the tree base, start growing when a tree is young. They can become quite large and are often dotted with leafy buds or shoots. They can also grow roots that help secure trees in thin or rocky soil.
The second kind grows on trunks in response to injuries, which can include viral or fungal infections. They start just above the damage and grow down to cover it, like a natural band aid.
Linden Lentz, a retired teacher and naturalist in Eureka, is so entranced by the enigmatic lumps that he often photographs and shares them online, including on his Facebook group Redwood Burls.
In Prairie Creek Redwoods State Park, Lentz spies the face of a human, or is it a Bigfoot, one of his friends asks on Facebook, on the Zig Zag Trail (see above).
Around the bend, he spies a strange bird (see below). What does it look like?
How about a Skeksis from the fantasy classic The Dark Crystal?
Other shapes fire the imagination: A dragon, a group of trolls, Jay Leno’s profile and this odd wonder (below), to name a few.
No need to explain what it looks like.
A third variety of burl, generally higher on a trunk, produces shoots and roots should silt partially bury a redwood in a floodplain.
Basal burls seem to be the result of genetics, whereas the other two kinds are responses to environmental stresses. Almost all burls, which can weigh hundreds of pounds, are covered by bark, even if underground.
No matter their shape or size, redwood burls certainly provide memorable moments as they fire up the imagination. See more and share your reactions on them on Lentz’s Facebook group Redwood Burls.