Spruce trees are of the genus Picea, which is made up of over 35 species of coniferous evergreen trees from the family Pinaceae. Evergreen is a term to describe plants that retain their green leaves throughout the year. Coniferous refers to plants that bear their seeds in cones or as yews, a specialized seed that is carried in a berry-like fruit called an aril. Spruce trees are coniferous in that they bear their seeds in cones. Spruce trees can be found all over the world in temperate climates, which includes all of the United States.
Spruce trees are large and, depending on the species, can grow anywhere from sixty feet to over two hundred feet. The largest spruce, the Sitka Spruce, can grow upwards of three hundred feet tall. Spruce trees have a cone-like, traditional Christmas tree shape, with the branches becoming more narrow as they reach the top. According to Softschools, spruce trees grow quickly, sometimes as fast as sixty inches a year. Spruce tree needles are attached to the branch singly in a spiral pattern around the branch. Needles are shed every four to ten years and leave the branches rough when bare, a trait that makes spruce trees easy to identify.
Spruce trees reproduce through cones. Each tree produces both male and female cones, the male cones carrying pollen are significantly smaller than the female cones carrying ovules. Wind carries the pollen from male cones to female cones, and female cones will release mature seeds as long as three years after pollination.
In the proper conditions, spruce trees can live for a few thousand years. The oldest known living spruce was called Old Tjikko, a Norway Spruce that is believed to be over nine thousand five hundred years old. Old Tjikko has not been the same tree alive for all those years, but rather the result of fascinating processes called layering and vegetative cloning. Layering is when a branch comes in contact with the ground, and subsequently the tree sprouts a new root. Vegetative cloning is when the trunk and branches of a tree die, but the roots remain alive to sprout a new trunk. Old Tjikko likely utilized both these methods in order to survive for so many thousand years. Regardless, Old Tjikko’s current trunk is estimated to be several hundred years old.
Spruce trees of all species are often used in landscaping, as they have such a visually pleasing silhouette. The one pictured above is a juvenile spruce that can be found along the path next to Hoyt.