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How to Identify Spruce Trees
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What are coniferous evergreens?
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Hi, I'm Danila James, and you're tuned to About.com. Today, we'll learn how to identify spruce trees.
About Spruce Trees

Around 35 species of this graceful evergreen, in the genus Picea, grow around the world, and especially in northern forests. Spruce wood is lightweight yet strong, and was the material of choice for the Wright Brothers when they built the world's early aircraft. By looking at the tree's needles, cones and branches, we can quickly distinguish a spruce from other conifers, like pines and firs.
Spruce Versus Fir Trees

Spruces are coniferous evergreens, which means they have needles which remain on the tree year round. Let's take a look at a branch. We can tell this tree isn't a pine because the needles grow out the branch individually, and not in clusters. Spruce and fir branches may look similar, so let's pull off a couple needles to distinguish them. Spruce needles are either square or triangular in the cross section, which means you can easily roll them between your fingers. Fir needles are flatter, and won't roll between your fingers.

Looking closer at the branch, we can see that spruce needles grow out of little pegs called the pulvinus. When the tree sheds its needles, these pegs remain, leaving the branches rough and bumpy. Firs needles, on the other hand, grow out of what look like small suction cups, which fall out with the needles, leaving the branches smooth.
Spruce Tree Cones

Next we'll take a look at the cones. Each cone is made up of a central stalk and scales that come off it. The scales on a spruce cone will be much thinner than those on a pine cone, and should feel paperlike and thin. You may be able to flake them off the stalk. Spruces and pines both retain their cones for several years, so you may see older, opened cones in the tree branches. Fir cones, on the other hand, lose their scales every year, so you will only see the central stalk attached to the tree.
Spruce Tree Shape

Finally we'll take a look at the tree shape. By shape and size alone, it may be difficult to distinguish a spruce and a fir. Both appear conical, and close to the classic "Christmas tree" shape, especially before they are fully mature. Pines, on the other hand, may lose their lower branches, and may have thinner foliage.

Thanks for watching. At this point, you should be well equipped to distinguish a spruce from other evergreens. Perhaps you can apply your knowledge on a trip to Sweden, where scientists have discovered a patch of Norway Spruces over 9000 years old. To learn more about tree identification, visit us online at About.com.
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