Why is there usually a yew in many churchyards?

Yew have long been associated with religious worship. So it is likely that churches were originally built near the sacred trees rather than the other way round. These trees live longer than any other species in Europe and can grow to an enormous size. Many are thought to be well over 1,000 years old. Yews were revered by the druids of ancient Britain, France and Ireland and no doubt early Christian missionaries preached in the shelter of the trees before their first churches were built.(questions and answers)