Kiidk'yaas or Kiid K'iyaas ("ancient tree") was a sitka spruce tree, Picea sitchensis var. aurea, that grew on the banks of the Yakoun River in Haida Gwaii (Queen Charlotte Islands), British Columbia. It had a rare genetic variation causing its needles to be golden in colour.

It was revered by the Haida First Nation living on the island. In their lore, when their ancestors had mistreated each other, the Creator had buried their village under snow. An old man and a boy hid under a cedar plank, and then fled up the Yakoun River. The old man warned the boy not to look back, but he disobeyed and was turned into the golden spruce. It was said that the tree would be admired until the last generation.

On January 22 1997, a 48-year-old unemployed logger named Thomas Hadwin surreptitiously felled Kiidk'yaas as a political statement against logging companies. He was later arrested, but mysteriously disappeared before he could be brought to trial.

The act shocked the Haida community; the elders felt they had failed to protect the tree adequately, and some were concerned that the prophecy that the tree would be admired to the last generation meant that the present generation of Haida would be the last.

However, in 1977, a group of botanists from the University of British Columbia had visited Haida Gwaii in order to take cuttings from Kiidk'yaas. They had been grafted onto an ordinary sitka spruce, and then grown separately, resulting in golden saplings. The trees were growing in the UBC arboretum.

Upon hearing of the tree's destruction, the arboretum offered one of the young trees to the Haida to replace Kiidk'yaas. The Haida accepted, planting it near where Kiidk'yaas had stood, and attempted to propagate approximately 80 parts of the felled tree as well.

See List of famous trees.