Tree of the Month: River Birch
Birches are generally known as trees of the north. One species claims the title of Finland’s national tree (Finland is a very cold country) and certain birches can be dominate in single-species swaths in cold places where others species simply can’t survive. Conversely, most birches do not do well with heat stress and quickly show signs of disease. So could it be that our region, with annual periods of rather stressful heat, will never see the beautiful bark and unique character that the birch brings? Enter the river birch (Betula nigra), the “Birch for the South” and the “Dry Site Contender.” With a native range spreading from New England west to Minnesota and south to Texas and Florida, this is no pansy birch that withers at the site of a hot sun. Indeed, the river birch claims wet sites and the river’s edge as its stronghold but it is in fact a species able to succeed in a breadth of conditions. While a young tree planted on a drier site will need a little love and care during establishment, once it has grown out a decent root system, the river birch should be able to find all the water it needs. Its tolerance to drought and heat are part of why it has become the birch of choice for landscaping around the country, and the only choice for the south. The tree is fast growing, commonly to heights of 60 feet.
The bark of birches is so interesting that it has entire books written about it (and entire books written on the bark itself!) Indeed, the bark of some birches can be peeled in continuous strips and makes for an excellent waterproof paper. In fact, Thomas Jefferson is quoted in a letter recommending birch bark as a superior paper for taking field notes in wet conditions. Other things made from birch bark include traditional canoes, boxes, bowls, and lamp shades. Birch bark has some unique oils and compounds that make it both waterproof and flammable. If you can find a fallen one when camping, harvesting the bark will give you nature’s own lighter fluid for the camp fire. For landscape value, the pink peely bark of a young river birch is a unique and very attractive feature. With age, the bark becomes darker and forms thicker plates that are still quite appealing. But the birches beauty and interest do not only run bark-deep – birch sap and wood have their uses too. The sap of some birches, including our river birch, can be tapped and used for a nice drink or boiled down to syrup. (“Would someone pass the birch syrup for my waffles?”) The wood is prized as a medium to light weighted wood that is quite sturdy. It is excellent for carving and has a number of carpentry and furniture-making applications. As for wildlife, the seeds support bird populations. Be sure to enjoy the look of its “catkin” flowers in the winter and spring!
Many people are discovering the value of trees for soaking up rainwater that otherwise might flood their yard, overflow their sewers, and push pollutants into their waterways. And many in our area are finding that the river birch is one of our best options as a tree to incorporate into water retention efforts. When planted as part of a “rain garden,” water can be channeled to the river birch, allowing it to thrive and putting it to work soaking up water. In times without rain, the tree is able to remain healthy, even on sunny, hot sites. Urban storm water management is a daunting task and the opportunity to stop the water at the source should always be capitalized upon.
The river birch has much to give us in beauty, as well as interesting products and services. It is also an ecological contender that will prove it’s self in urban plantings. Come see some examples of this tree growing happily in a rain garden setting at our headquarters in Brookland, or at these sites near you: