I first learned of Black Spruce (Picea mariana​) through my friend Maya, an aromatherapist who has given it to me numerous times as essential oil - simple and in blends.  I really enjoyed it that way and used it on troubled joints.  Various parts of the tree have been used by Native Americans for skin, internal ailments, diarrhea, burns, rashes, scabs, sores, toothache, venereal disease, wounds, respiratory infections, digestion, kidneys, stomach pains, and infections (Moerman Native American Ethnobotany).

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The Divine Farmer's Materia Medica lists Gardenia, Bamboo (foliage), Phellodendron, Wuzhuyu, Mulberry (root bark), Elm (preparation of fruit), Bitter Orange, Magnolia (Houpo - Magnolia officinalis & spp.), Ash, Prickly Ash, Dogwood, Chinese Trumpet Vine, Umbrella Polypore, Jujube (thorns), Longan, Lily Magnolia (Mulan - M. liliflora), Mulberry Mistletoe, Weeping Willow (catkin), Winged Wahoo, Mimosa, Usnea, Ganqi, Shinan, Creeping Prickly Ash, Goldenrain Tree (flower), Baisuichengzhongmu ("Tree In The Midst Of The Hundred Year City")...