Much has been written on trees in magical folklore and Paganism. This post will concern these trees in relation to cemeteries, souls of the dead, and their uses in death witchcraft and necromancy.
Many of these trees are used for wands and talismans in death magic. A branch can be picked up from the ground of a cemetery and polished into a powerful tool. If you understand the associations, you may grind their bark for protection powders, give their dried leaves as offerings, and include them in talismans.
These particular trees are common in North America where I live, though you can find many more online. Along with their mythological symbolism, many of these trees are planted in cemeteries because they require little upkeep to survive. However, this only highlights their association with endurance, hardiness, immortality and rebirth.
Note that these trees have many more associations and folklore attached to them. I am focusing on what I can find that connects to death, resurrection, and the afterlife.
In the best case scenario, a magician will learn to recognize these trees on sight. Otherwise, they may recognize some of these trees in a cemetery, and gain a better understanding of the conditions of the souls beneath the canopy. They can also use these trees for their own magical purposes.
For more information on plants and trees common in North American cemeteries, you can visit this document from the Greater Metropolitan Cemeteries Trust, April 2016.