White barked birch trees are easily among the most beautiful of landscape trees for use in Minnesota and most northern tier states. There are a number of good varieties now available, including Renaissance Oasis Paper Birch, Renaissance Reflections Paper Birch, Dakota Pinnacle Birch, Parkland Pillar Birch and Whitespire Birch.
Many people shy away from these birch trees because they believe them to be short-lived. This is due primarily to the attacks on white barked birch trees by the bronze birch borer insects which tunnel around under the bark and slowly kill the tree. stressed trees are most vulnerable to attack, but happily there is a quick and easy way to protect these trees by applying a one minute, once a year dose of the systemic insecticide imidacloprid.
Imidacloprid is very easy to apply. Simply mix a few ounces with 1 1/2-2 gallons of water, and slowly pour on the soil immediately next to the tree trunk. You are done for a year. Repeat this easy one minute treatment a year later. The stunning beauty of your white barked birch will endure for years with the quick and easy bit of maintenance.
Be sure to treat white barked birch trees even if literature you see claims resistance to birch borer for a certain variety. In our experience, only River Birch trees are truly resistant to birch borer, but unfortunately they do not develop the beautiful white bark.
We only recommend the use of imidacloprid for plant materials that are not pollinated by bees. Avoid the use of imidacloprid on all flowering plants to reduce negative impact on pollinating insects such as honey bees and many of our native bees.
At our nursery we have several formulations available to help protect the white barked birches and other plants not pollinated by bees. If you want a really beautiful landscape tree, you may want to try Oasis Paper Birch or Dakota Pinnacle Birch or one of the other varieties that quickly turn the bark color from green to brown to white as they grow vigorously.