The river birch is a medium-sized deciduous tree extending from New England, west to Kansas. Used as a forest buffer and to assist in erosion control along stream banks, the river birch also provides food for many bird species, including grouse and white-tailed dear. River birch bark is light brown to buff in color and thin like paper. The leaves are double serrated and wedge-shaped with sharp points. The river birch is found growing along swamps and prefers fertile and moist soils with a pH between 4.0 and 6.5. It requires full sun and is very intolerant of shade.
Prune the river birch in the summer months after sap production has ended. River birch trees are "bleeders" and cannot be cut or pruned while the tree is producing sap. Pruning in summer will produce hardy growth the following season.
Remove the top stems of the birch using pruning shears. Maintain one strong shoot leader to encourage the birch to grow tall and straight. Cut back all side or lateral branches that are twisted and weak.
Remove all damaged or diseased stems and branches by cutting off the entire branch. Remove all insect-infected branches to avoid infecting the tree.
Prune young river birch trees to one main branch, keeping two or three saplings on either side. Remove all sucker shoots, which stem from the base of the tree to free up available nutrients for the main sapling branch.
Periodically check your tree to ensure it's strong and healthy. River birch trees are prone to aphid infestation in the early spring, so if you suspect an infestation, contact your local county extension office.