Spruce burls in the Olympic National Park, Washington State
The rounded knobs are tumors. Damage to a tip or bud of the Sitka spruce caused growth cells to divide more rapidly than normal to form these swellings or burls.
Chemically the same as normal wood, a burl is technically not a cancer.
The nearby ocean seems to be a factor. Possibly an attacking bud worm triggered the change, perhaps by carrying a virus or an inorganic compound from the salt spray into the tree.
These burls are sold in a high price.
Spruce burls in the Olympic National Park, Washington State
The rounded knobs are tumors. Damage to a tip or bud of the Sitka spruce caused growth cells to divide more rapidly than normal to form these swellings or burls.
Chemically the same as normal wood, a burl is technically not a cancer.
The nearby ocean seems to be a factor. Possibly an attacking bud worm triggered the change, perhaps by carrying a virus or an inorganic compound from the salt spray into the tree.
These burls are sold in a high price.