Saturday, January 11, 2020

The Red Spruce tree (Picea rubens)

For this week's look at various trees that we plant at Replant.ca Environmental, I'm going to focus on the red spruce.  As is common with many different tree species, this one is known by many names.  The other names that I'm most accustomed to hearing are eastern spruce, Maritime spruce, and yellow spruce.  The Latin name is Picea rubens.

Red spruce is an extremely common and valuable tree in eastern Canadian forestry.  Due to its versatility and economic value, it is the most commonly planted tree in the Maritime provinces.  Although it isn't the fastest-growing conifer, it is considered to be a late succession tree.  This means that it "catches up and wins," like the tortoise in the fable of "the tortoise and the hare."  The red spruce can often live to be 250-400 years old.


When the red spruce is young, it prefers to grow in moist soils.  It helps if the groundwater moisture is aerated.  Well-drained soils, or soils that are moistened by flowing water, are ideal.  However, red spruce is quite versatile, and will still thrive in many other types of ground conditions.  Red spruce is quite biologically similar to black spruce (a species which does really well in swampy areas with more stagnant water).  Red spruce is also extremely shade-tolerant when it is young.  This is important, because spruce trees generally grow more slowly than other conifers (such as pine) for the first decade or two.  Due to this slower start, spruce usually fail to get above competing grass and vegetation for several years.  However, they don't usually get choked out by plant competition due to their shade tolerance.

When a red spruce matures, it can be twenty to twenty-five meters in height (seventy to eighty feet).  A mature tree will often achieve a DBH (diameter at breast height) of 50cm to 60cm (up to two feet).  Red spruce often grows straighter than conifers such as red pine and white pine.  Although the red spruce doesn't grow as large as an eastern white pine, it's a beautiful and long-lived species in its own right.  Perhaps this is why the red spruce is the provincial tree of Nova Scotia.

Red spruce is mostly an eastern Canadian and northeast US seaboard species.  Here's a range map, courtesy of Wikipedia:


Spruce needles and balsam fir needles often look very similar to someone who doesn't spend a lot of time in the woods.  However, there's a neat trick that you can do to distinguish between them.  Spruce needles are four-sided.  When you put a needle between two fingers and try to "roll" it, it rolls easily.  Balsam fir needles are three-sided but their shape is like a very flattened triangle.  Due to this shape, balsam fir needles don't roll easily between your fingers.  This trick can still be a bit confusing.  If you use a lot of pressure, it's still possible to "roll" the needles of a balsam fir.  And if the spruce needles are sticky or if your fingers are rough, they don't necessarily roll perfectly.  However, if you are out in the woods and see two trees that look slightly different, and you think one is a spruce and one is a fir, try the needle-roll test.  Also, try grabbing a branch and squeezing.  Be careful though!  Spruce needles are much more pointy at the ends, so they'll feel a lot more prickly than fir needles.

If you're looking at the trunk of a juvenile tree, the appearance of spruce and fir are quite different.  Spruce trees will look scaly, and usually have a yellowish-brown or reddish-brown colour.  They will also have more needles on the trunk.  Conversely, a juvenile balsam fir tree will usually have grey bark, and it's usually quite smooth with almost no needles, except maybe some spare needles on the top foot or so of the tree.  The bark of each of these trees becomes much more rough as the trees passes the juvenile stage.  Both types of trees will develop vertical furrows on the bark, although the furrows will be more pronounced on spruce trees.

Take a close look at the underside of this red spruce branch.  What obvious colour patterns do you see?


When you look at a red spruce branch on a young tree, the new growth has a yellowish tinge, and the older growth has a brownish tinge.

Here are four interesting facts about the red spruce:

1.  This tree is monoecious.  This means that individual flowers (cones) are either male or female, but both sexes can be found on the same tree.  The cones are cross-pollinated by wind.

2.  Red spruce trees do not do well in areas with high atmospheric pollution, or "acid rain" (rain contaminated by industrial smoke and chemicals).  This is one more reason to keep our earth clean.  There's a slogan that says, "The solution to pollution is dilution."  I think a better solution is to avoid polluting in the first place.

3.  Red spruce is the most sought-after wood for making most musical instruments.

4.  Spruce twigs can be boiled with sugar, and the resulting liquid can be used to make spruce beer.  I think a lot of people would prefer spruce beer to hemlock tea.


As I mentioned, the red spruce is the most economically valuable species in the Maritime provinces, and is planted very frequently in post-logging operations.  Unfortunately, in that type of work, the logging companies generally plant it as a monoculture.  At Replant.ca Environmental, we endorse biodiversity.  Red spruce is definitely an important species within our planting mixes, but we never plant it by itself.  Here's a photo of some of our red spruce seedlings:



Thanks for reading ...

- Jonathan Clark
www.replant-environmental.ca



Replant.ca Environmental is a Canadian company that plants trees for carbon capture and builds community forests.  We also plant trees in national, provincial, and municipal public parks to mitigate damage from wildfires, storms, insects, and forest diseases.  We operate thanks to numerous small contributions from the general public, in addition to larger project sponsorships from businesses and corporations around the world.  If you'd like to learn how to show your support, visit our donations page.  Even if you aren't able to make a contribution, we very much appreciate when people are able to share our posts or our website link on social media, to help spread the word about the work that we're doing!

Teachers are welcome to use content from this post for their classes.  If you know a teacher who might like to use this information, please share it with them!  The more that people learn about trees, the better our world will be.

To learn more about the various species that we plant, visit the conifers page or the deciduous (hardwoods) page on our website.  Thanks so much for your interest!




Incidentally, our organization is often seeking additional land for our carbon capture projects.  Please visit this link if you might know of a recently-harvested property that we could rebuild into a permanent legacy forest.