It's still winter in Louisiana. Most of the trees are leafless. It's a good time to appreciate the diversity of tree bark in the arboretum. Our tree of the week is identified primarily by its bark. You might see the river birch (
Betula nigra) around town, planted as an ornamental tree in lawns and commercial landscapes. In the long hot Louisiana summers the leaves of the river birch provide much needed shade for our buildings and sidewalks. Now that it's winter, the leaves are gone, revealing the interesting form of the tree and its characteristic peeling-flaky bark.
There is one river birch in the arboretum collection. In 1985, two river birches were purchased from Clyde Gorum's Nursery in Shreveport. They were planted on the south side of the long wooden bridge. Ten years later, in 1995, one of the two trees was buried two feet under an embankment that was constructed around the lower pond. The tree survived and is thriving today. It's companion was removed in 2007, due to extensive insect damage.
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| The river birch, over 30 years old, is growing in the corner of the embankment overlooking the arboretum's drainage basin. The leaves of two tree palmettos (Sabal palmetto) are partially obscuring the divided trunk of the river birch. |
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| This is one tree with multiple stems. |
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| The tree was planted before the embankment was constructed. In 1995, approximately two feet of dirt was piled up around the base of the tree to construct this wooden retaining wall. The tree didn't have a problem with the extra dirt. |
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| Here we are standing in the drainage basin flanked by tree palmettos. This picture shows the river birch's tripartite trunk. |
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| The river birch and wooden railing have grown very close over the years, perhaps too close, with the river birch complaining of needing 'space' and the railing complaining about being leaned on too much. |
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| This is the characteristic river birch bark. It's shaggy, peeling, flaking, and rough. The top layer of bark is grayish-white, and it peels back to show a reddish-orange layer. This section has been worn off by the long, heavy palm leaves of the tree palmettos. |
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| This is another look at the shaggy, peeling, rough bark with hues of maroon and orange. The LSU AgCenter describes it as 'salmon colored'. Check out their pictures in the link below. |
For more information about the river birch consult the following links:
Louisiana Plant Identification and Interactive Virtual Tours (LSU AgCenter)
Virginia Tech Dendrology
U.S. Department of Agriculture, Forest Service
United States Department of Agriculture
