It's about grief, and loss, and the cycle of life in nature. She's lost her grandfather, but he was thinking about the future when he died -- he planted the trees that he knew he'd never see bear fruit, because he knew his children and grandchildren would benefit. And in the end, she's looking at the trees as they grow, and thinking even when they're killed, the new wood comes up from the roots. She's comparing that to her family, saying they have deep roots that survive the death of any individual member. She's comparing the natural world, the land that her grandfather loved so much, with the world of people where she's lost her grandfather and many other relatives, but the cycle of life always goes on no matter what in both cases.
It's about grief, and loss, and the cycle of life in nature. She's lost her grandfather, but he was thinking about the future when he died -- he planted the trees that he knew he'd never see bear fruit, because he knew his children and grandchildren would benefit. And in the end, she's looking at the trees as they grow, and thinking even when they're killed, the new wood comes up from the roots. She's comparing that to her family, saying they have deep roots that survive the death of any individual member. She's comparing the natural world, the land that her grandfather loved so much, with the world of people where she's lost her grandfather and many other relatives, but the cycle of life always goes on no matter what in both cases.