This is one of my all time favorites, played acostically by the Grateful Dead. It is about death of a man, Neil Cassidy and the birth of another, a baby girl, Cassady Law.
Bobby Weir was working on the song while Eileen Law was preparing to give birth in the home they shared, and John Barlow wrote the lyric with the death of Neal Cassady and the birth of Cassidy Law in mind.
The lyrics: "lost now on the country miles in his Cadillac," and "wheel to the storm and fly" are especially reminiscent of jack Kerouac's recollections of the long road trips with Cassady in his book "On The Road." Kerouac even tells the story of their trip to Chicago in a Cadillac which incidentally got stuck in the mud on a country road.
The lyrics "child of countless trees" likely referred to when Neil died while trying to count the number of railroad tied between two locations in Mexico. A bet that he made with Kesey or somebody. He was apparently very high on speed at the time and the hot sun was too much for his heart.
Death of one and the birth of another, an ending and then the hope and promise in the creation of new life, for me Cassidy is an anthem, I can not listen to it without it moving me, no matter how often I have heard it.