How to Identify Minnesota Native Conifers
Lisa Olson, Master Gardener
The garden beds are tucked in under an abundant blanket of snow. The wardrobes of the deciduous trees are a distant memory after their yearly fashion show. But for some of us, one of the most beautiful sights this time of year, is the star of the season’s show: the coniferous tree. Most conifers stay green throughout the winter but they are not all the same.
It’s February in Minnesota. The dead of winter as they say. The garden beds are tucked in under an abundant blanket of snow. The wardrobes of the deciduous trees are a distant memory after their yearly fashion show. Many having changed from vibrant spring green all the way to the glorious colors of autumn, finally turning brown and floating to the ground to nourish the soil, leaving the trees bare and waiting for the next phase of the cycle to begin again. Many gardeners are dreaming of their favorite plants that will spring back to life again when the warming sun melts away the chill of winter.
But for some of us, one of the most beautiful sights this time of year, is the star of the season’s show: the coniferous tree. Though not synonymous with the word evergreen, most conifers in Minnesota do remain green throughout the changing seasons, providing a welcome contrast of color against the white and gray landscape. Note, there are many tropical plants in warmer climates that are evergreens in that they stay green all year, but they are not all conifers. This article will help you identify the lovely conifers native to Minnesota.
First of all, it is important to note the difference between conifers and deciduous trees. All trees have leaves, but the leaves of conifers are needles. The other obvious difference is that all conifers have cones to hold their seeds, unlike the various seed covers deciduous trees possess. Many people incorrectly call all cones pinecones, but not all conifers are pine trees. All deciduous trees drop their leaves in winter. It may seem surprising, but conifers lose their needles too. For most conifers, however, it happens over a very long period of time. Rather than drop all of their needles at once like deciduous trees lose their leaves, it may take many years for a conifer to gradually drop and replace all of its needles.
There is an exception though, and that is the Tamarack, also known as the eastern or American larch. Each fall, the Tamarack turns a dull yellow in the fall and loses all of its needles just like a deciduous tree loses its leaves. Its cones release tiny winged seeds from its cones which often remain on the tree for years.
Besides the Tamarack, there are nine other conifers native to Minnesota. They are all true evergreens, slowly changing out their needles over a number of years. Two of the native conifers are cedar trees. One is the eastern red cedar, which is actually a juniper, and the other is the northern white cedar.
1. Eastern red cedar (actually a juniper): The needles on the red cedar are scale-like with four rows lining up along the stem making it appear almost square. Its ¼ inch blue berry-like cone holds one or two seeds that are a bird favorite.
2. Northern white cedar: The scale-like needles on the white cedar are arranged in such a way that they appear to form small flat branches. The cones are ½ inch oblong yellowish-brown that grow singly or in clusters at the ends of the branches.
3. Balsam fir: It is very popular as a holiday tree with its dark green, ½ -1 inch long flat, rounded-tip needles. Its cones are about 3-4 inches long that stand upright on the branches. When it ripens, the seeds fall along with the scales protecting them. What’s left, is the empty inner core of the cone, standing straight up like a spike.
4. Hemlock: The shade-loving hemlock has needles that are about 1/3-2/3 inches long. They are flat and blunt. The cones are ½-3/4 inches long. They hang from the ends of twigs. The hemlock is just barely native to Minnesota, reaching the state up north just south of Lake Superior.
5. White Pine: The white pine has 2 ½ - 5 inch long needles that are bluish-green on one side and white-ish on the other side. They grow in bundles of five and they are incredibly soft. The cones are 4-8 inches long.
6. Jack Pine: The jack pine needles are ¾ to 1 ½ inches long that are flat and stubby and grow in bundles of two. The cones are 1 ½ - 2 inches long. They are curved, brown-ish when ripe, and its not uncommon to find ripe seeds on the tree for many years.
7. Red Pine (also known as the Norway Pine – the state tree of Minnesota): The 4 - 6 inch long needles of the red pine also grow in clusters of two. If you bend a needle, it makes a clean break. The interesting cones are about 2 inches long and light brown. While they mature and drop their seeds in early fall, the cones remain on the tree until the following spring.
The last two native conifers are the black spruce and the white spruce. Spruce needles are unique in that they are square shaped. You can pull off a singularly grown needle and roll it in your fingers due to its square shape. The needles of the white spruce have an unpleasant odor when crushed.
8. Black Spruce: The cones of the black spruce are ½ - 1 ½ inches long and they start out dark purple and change to brown when they are ripe.
9. White Spruce: The cones of the white spruce are about 2 inches long with a slender appearance.
While you may be familiar with names like Fraser Fir, Doulgas Fir, Scotch Pine, and Colorado Blue Spruce, these popular trees commonly used over the holidays, are not actually native to Minnesota and so were not featured in this article.
In closing, however, here is a summary to at least help you differentiate between fir, pine, and spruce trees:
Fir: Needles are flat and soft. (Remember “friendly fir” - if you were to shake its hand compared to a pointy, stiff spruce.) If you were to pull off a needle, which grows singularly, it would leave a small circular scar on the stem.
Pine: Needles group in clusters of two, three, or five depending on the type of tree. The clusters of needles are called fascicles. Most pine cones are woody in texture.
Spruce: Spruce needles are sharply pointed, square, and you can roll them between your fingers. They are attached singularly to the stem on small woody structures that remain as projections if you pull a needle off the stem. Spruce cones are generally more flexible than pine cones.
For more information, The University of Minnesota has put together this handy booklet: A Beginner’s Guide to MINNESOTA TREES. https://conservancy.umn.edu/bitstream/handle/11299/49816/6593.pdf?sequence=1&isAllowed=y
https://www.dnr.state.mn.us/trees/native-trees.html (including all photos, except where noted)
Photo credits: Lisa Olson (1), Minnesota DNR (2 - 12))