Minnesota's native cedars

Last week I talked about observing chickadees snatching sunflower seeds from the feeders and flying quickly to the safe haven of the lone white cedar that sits on the ridge outside my sunroom window.

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Cedar was one of a just few that dot my land and that this year the cedar is particularly noticeable because of its abundance of cones. The small, delicate, light brown fruits form clusters weighing down the scale-like leaves, which look flat and almost fan-like.

If you crush the leaves they would emit a pleasant, aromatic scent--a trait of most cedar species. It was just after saying I love the smell of cedar that my mind slipped from the topic of trees to memories associated with the aroma of my ma's cedar chest.

Lost in my own reverie and rambling, before I knew it, I ran out of column space. So today, I return to the subject of cedar trees.

Cedar was and still is used to make memory chests, although the real purpose of storing items in a cedar chest is protection from mildew, moths and other insects injurious to linens. The natural oils in cedar have been used as an insect repellent for centuries.

Interestingly, while all cedars contain the oil, the ability to repel insects varies by the species and even by the individual tree. According to one reference, soil and climate also influence the aromatic qualities of cedar.

Eastern red cedar is the most fragrant and one of the best for discouraging little cloth-eating creatures. Western red cedar and yellow cedar fall far below the standard in that department, and the white cedar like I have sitting on the ridge, is not even an insect-repelling, chest-making candidate.

When I started thinking about cedar, I inspected the cedar-lined wall in one of my closets. It surely didn't have the aroma of my Ma's cedar chest, but then again the closet isn't air tight so that's to be expected. I did note some crystallization on the surface of the smooth boards and was curious about it.

In researching material for my column, I learned that over time, the oils tend to crystallize on the surface of the wood, thus reducing the fragrance and repellent capabilities. The solution is to lightly sand the wood with 100 grit or higher sandpaper. This will "open the pores" of the resins and restore the qualities sought. If sanding doesn't seem to affect the smell, then a coating of natural cedar oil extract may be applied.

Minnesota has two native species of cedar--the white cedar, also known as arbor vitae, and the red cedar, which is often called juniper. Let's take a closer look at the duo.

White cedar (Thuja occidentalis) grows predominately in the northern part of the state, thriving in moist places where it is often found in dense pure stands. Sometimes, however, it may grow on stony ground, singly or in small clumps as far south as Winona County in the southeastern corner of Minnesota.

Its form is compact and pyramidal, with a strongly tapered and often twisted trunk. Frequently, the trunk divides into two or more direct stems. Branches are relatively short and nearly horizontal, sometimes forming almost impenetrable thickets. Dead branches are very stiff and persistent.

I have one long, lower dead branch on my cedar that I never prune because it is the absolute favorite perching spot for the hummingbirds. The little hummers fly to and from the feeder from the branch. The stark branch provides a great view of the hummingbirds at rest, so unless the branch falls off on its own, it'll not see the likes of the chainsaw.

The bark of the white cedar is gray to reddish brown, with a tendency to separate into long, vertical, narrow shreddy strips. Leaves, like I mentioned earlier, are scale-like, flat and fragrant.

This species may sometimes reach a height of 70 feet. Its wood is light, soft, brittle, coarse-grained and pale brown in color. It is also durable and used in making canoes, fence posts, railroad ties, telephone poles and shingles. Fruit extracts and tinctures are made from very young branchlets.

There are numerous ornamental varieties of white cedar sold through nurseries. It is often referred to as arbor vitae in the landscape trade.

Red cedar (Juniperus virginiana) grows on dry, gravelly soil and along rocky ledges in the southern half of the state. It's most abundant on river bluffs in the southeastern part where few other trees are found.

In comparison to the white cedar, it's shorter in stature, growing with a straight trunk to a height of 25 to 30 feet under ideal conditions. In poor, rocky and dry soils, the form differs and the trunk may be very divided or nearly prostrate. The thin, reddish brown bark peels off in long, vertical shred-like strips.

There are usually two kinds of leaves found on the same tree. More common are the dark green, minute and scale-like leaves that clasp the stem in four ranks so that the stem appears square. The second kind of leaf usually appears on young growth, on vigorous shoots or on branches in deep shade. These are awl-shaped, sharp-pointed, spreading and whitened on the underside.

Many ornamental varieties of junipers are offered for sale through commercial nurseries. They are often part of landscape designs due to their hardiness and interesting forms, but when I worked in the nursery trade, I personally avoided the plant because I develop red, raised, itchy bumps when I come in contact with juniper branches.

The fruits are small dark blue, berry-like cones that encase one or two seeds in the sweet flesh. Juniper "berries" are a favorite winter food for some birds.

Wood of this species is red, fine-grained, soft, weak and like its kin, fragrant. It too is very durable and may be used for interior woodwork, chests, closets, lead pencils, posts and poles. The oil of red cedar is distilled from the leaves and wood.

On the negative side, red cedar spreads cedar apple rust. Consequently, it should not be planted in or near orchards or anywhere in regions devoted to commercial apple production.

So, there you have it--a small snapshot of the native cedars of Minnesota. Now that my column is complete, I think I'll find some sandpaper and do a little roughing up of the cedar boards in my closet to restore their aroma.

[Source: DNR Forestry materials]