Betula nigra, or river birch, is a popular urban tree in much of the United States. It is fast-growing and hardy to USDA zone 4. River birch grows to 70 feet tall and has an oval or pyramidal shape. It will thrive if planted properly in a suitable site.
Choose a sunny location. River birch prefers rich, moist, acidic soil, but will not tolerate constant wet feet. It is heat-tolerant and can survive modest droughts.
Dig a hole twice as wide as the root ball and as deep as the container. Mix some organic material--peat moss, leaf mold, manure or compost--into the soil that has been removed. The ratio should be 1/3 organic matter to 2/3 soil.
Remove the plant from its container. If the roots are a dense mass, score the root ball deeply in three places with a pruning saw--this will help prevent girdling. Prune any visibly damaged roots.
If the plant is balled and burlapped, place the tree in the hole before removing the wrapping. Remove as much of the wrapping as you can, and remove all of the string. What is left of the burlap will disintegrate over time.
Fill in around roots with the mix. When you have filled in the hole halfway, fill it with water. As the water drains, it will settle the planting mix around the roots. Continue filling in the hole and water again.
Water every day for the first two weeks, then weekly for the first year while the tree is actively growing. Once established, river birch will be more tolerant of dry conditions.