There is one little Australian plant that does what the yew does, i.e. root from it's branches and spread. For years no one understood why the Australian Aboriginals revered this plant. With this Aussie plant the center dies and so you get a ring of the plants that grows with each generation. Because they are all root from the same parent they are all technically clones and therefor still the same living organism. Some are estimated to be 10,000 to 15,000 years old!

Again, the longevity and rebirthing of this plant probably makes it so 'sacred'.