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Black Alder Tree - The Lady from the Wetlands

I would like to share my observations about plants, trees, shrubs and flowers that I see every day, so I will write about it every week giving various interesting facts about them.

Black Alder tree woody cones - December 2022
Black Alder tree woody cones - December 2022

Some time ago I went to a place near my house. Usually everyone rushes to the biggest park in the area and you can't evem find a place to sit on a bench for a moment. Crossing the street further, there is a completely different scene where there is always less hustle and bustle. There are ducks, Canada Geese, and other really wonderful birds that come to the shore as if they want to say hello to everyone who comes there.

Walking around a small lake in the place where I went, I noticed a black alder tree. At this time of year, nothing catches the eye like the brown cones of this tree.

Black alder is sensitive to droughts and water damage, but it is resistant to flooding, and can be submerged in water for many years. Over time, its wood hardens and blackens. Because of this I was not surprised to see this tree growing around the lake in the place where I was walking. Alder is common in lowland wetlands, but mainly along river banks and reservoirs and in forests, swamps and marshes. It is also often planted in urban areas as a tree of urban greenery.

Alder grows from 10 to even 40 meters. It also lives a very long time. Some believe that it can live up to 120 years, but I've read that it could live as long as 180 years.

Alder has many subspecies and names (there are about 50 of them). The wood of the tree is a yellow-white colour that becomes orange when is cut down.

Black alder has cones embedded on stalks that are very unique and eye-catching. Woody cones, after releasing seeds from them, can stay on the tree for many years. The fruit of alder is a brown nut.

In early spring, from March to April, the female flowers are red and the male catkins are green-yellow.

Looking closer at this tree, I noticed that its twigs are thin and the bark cracked.

Alder grows along the lake (The thin branches on the right site)
Alder grows along the lake (The thin branches on the right site)

In spring and summer, the leaves are oval or rounded and have tufts of hair on the underside. Surprisingly, these leaves remain green in the fall, and the tree loses them only between October and November. New shoots can grow from the dead trunk.

Black Alder leaves with beetles - Spring 2022
Black Alder leaves with beetles - Spring 2022

It is interesting that alder can also develop its root system under water, which allows it to spread, among others, over watercourses. Many creatures, such as otters and beavers often live under its roots and fish find shelter there as well underwater.

Black alder is very resistant to air pollution. Its other advantages include the ability to enrich the soil with nitrogen due to the symbiosis of its roots with nodule bacteria, which in turn are able to fix atmospheric nitrogen.

As you can see, this tree has only advantages, and if you add other surprising facts to it, you have to admit that this tree is extremely valuable.

In the past, alder wood, due to its water resistance, was used for buildings placed in water, for example those in Venice, as well as for the construction of locks and bridges. The high content of black and brown tannins was used in tanning and dyed materials.

Due to its healing properties, alder was also used as a compress for injuries, cone were used for stomach ailments, and the bark for coughs. In Europe, alder is used to plant trees on heaps in industrial areas, landfills and wastelands. It is also used to produce furniture plywood or parts for yachts and boats.

Nowadays, alders are planted on the banks of streams and rivers to prevent erosion, preventing the washing of the banks by water which destroys the edges.

Two towns in Germany owe their names to alders - Oelsa and Klein-Oelsa.

If you know other interesting facts about this species share it in the comments below.

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