Tuesday's Trees- River Birch, Betula nigra

I remember a number of years ago seeing a large ragged looking tree outside a garden center.  I was far from even thinking about tree postings, very young in my Master Gardener-ship.  My friend and I asked one of the people who works at this garden center what that tree was.  His response??  Yes, it was a River Birch.  No, it did not look like this one on the right.  The bark on a mature River Birch is not thin and papery and peeling.  The bark on a mature Betula nigra is dark, thick, and scaly.  He told us that most people don't realize how different the mature tree looks from the young tree.   Les?  Was that you all those years ago? 

People have a love/hate relationship with the River Birch.   This tree is a native to North America.  It is also one that many have cultivated varieties in their front yard.  I like the look of the young tree, I love the dappled light that filters through the many small leaves.  Ask someone who has a Betula in their front yard what they think of their tree.

 

This picture was taken along the edge of the lake that I live on, it is a naturally occurring tree.  The lake is fed by two rivers, now dammed, making the lake.  See all these small branches?  They are brittle and end up littering the yard, along with the leaves and in the spring-- the catkins.  This is my only negative on this pretty tree.  The name 'River Birch' comes from the location and habit of the tree.  It thrives along the water's edge.  While some of the reading I did says it does not need wet soil.  It is found along stream beds and floodplains because of the seed disbursement.  Betula nigra is one of the few early ripening seed trees.  These seeds drop early in the spring in the exposed mudflats and are carried downstream by receding high spring waters.  Seed production occurs almost every year.  All other birch produce their seeds in the fall.  Other trees that are early spring ripe seeds are Silver Maple and American Elm. 

This picture is representative of the spring's flowering of the River Birch.  I was only able to get a photo of the male catkins.  This tree is monoecious, both  male and female flowers on the same plant.  The pollen is one of the hay fever culprits.   The fruits mature as the leaves emerge.   The leaves are alternately attached, simple, oval, and double-toothed margins.  As young leaves their veins are quite noticable.  The leaves are darker on the top and lighter in color on the underside.    Their fall color is yellow to brown. 

This is the only native birch that is resistant to the Bronze Birch Borer beetle larve. 

A mature tree came be 80 feet tall in the perfect place, most commonly they are under 60 feet.  Their shape is a nice vase shaped and a rounded crown.  These trees can live 50 -75 years. 

Commercially the wood is not desirable.  Some use the River Birch for basket hoops, inexpensive furniture and turned articles.  According to the Silvics Manual they can be harvested for pulpwood with a mixture of other hardwoods.  The Silvics Manual is a wonderful reference website.  If you haven't visited this site, you should do so.  I share just the tip of the iceberg of information from this web resource.

I leave you with a couple more photos of the bark, the branches, and the bright blue sky.  In the right place, this is a wonderful tree, especially if you don't worry about little branches dropping in the garden.

The decorative bark is always a nice focal interest in the winter.  I am going to take a break from the tree posts for a while.  I have to build my photo library.  When we were in Virginia I had the Learning Garden with all the trees labeled.....now I am having to learn to make those dreaded identifications with book in hand. (with the help of a patient Extension agent who thinks I spend all my time wandering in the woods. )

©Copyright 2011 Janet. All rights reserved. Content created by Janet for The Queen of Seaford. words and photos by Janet,The Queen of Seaford.