Ask The Arborist: River Birch
I'd like to go by climbing a birch tree, and climb black branches up a snow-white trunk. Toward heaven, till the tree could bear no more, but dipped its top and set me down again. That would be good both going and coming back. One could do worse than be a swinger of birches.
-- Robert Frost, Birch Trees
Not to my surprise, river birches are one of the most popular landscape trees in the Omaha area and all for good reason considering their beautiful peeling bark, convenient medium size, and magnificent fall color. People have fallen completely in love with these trees, but of course just like any other tree it has its challenges, especially at this time of the year, so be sure to keep an eye on your most valued specimen. The issues that I have been seeing are treatable. Here are the most common:
Leaf Drop: Usually during the middle of a hot dry summer, birches get a little stressed and like to lose some of their inner leaves. This helps to conserve energy by preventing water loss through evapotranspiration. Be sure to check the soil around your tree to make sure that it is getting sufficient water. The river birch is aptly named. If there is a period of a long harsh drought don’t be afraid to give your birch a few minutes of watering a week until we get some rain. Mulching is also a good idea to keep the root system cool and moist.
Iron Chlorosis: Signs of a chlorotic tree are found on the foliage where the leaves are turning yellow but the veins are still green. This is caused by a combination of an iron deficiency and soil pH surplus for these trees that like a more acidic 6.0 to 6.5 range. Simple soil tests are available at your local nursery that can help to determine what range your soil is in. Soil amendments are also available and CM’s also offers an iron injection to help green up any tree that might be showing signs of chlorosis
Japanese Beetles: Even though birch trees are not Japanese Beetles’ first choice of a meal, I have been seeing them munching around on their delicate little leaves. These beetles are shiny green with brown wings and leave little holes all over the foliage. And if you find them in your trees they are most likely in other areas of your yard as well. Luckily their season is slowly coming to an end but if you still see them buzzing around there are a wide range of pesticides available that can fight them off. CM’s offers a spray containing bifenthrin that kills them on contact.
Please be sure that your tree is properly diagnosed before any treatments are made.