Spruce are trees of the genus Picea , a genus of about 35 species of coniferous evergreen trees in the Family Pinaceae , found in the northern temperate and taiga regions of the earth . A spruce is a tree of the genus Picea , a genus of about 35 species of coniferous evergreen trees in the Family Pinaceae , found in the northern temperate and boreal ( taiga ) regions of the earth .