The Best Trees to Plant to a River Bank
River banks are important and sensitive habitats. They are subject to flooding, soil erosion, soil deposition and rechanneling. The river water carries chemicals and other substances to and from the area being planted. Riverside plantings provide habitat to native wildlife, supplying not just food and shelter but a corridor for wildlife movement. The best trees for river bank planting are native species which have good root systems, could withstand flooding and possible periods of continuous humidity, provide good wildlife habitat and don’t possess the invasive tendencies of several exotic species.
Large Trees
Two large trees growing to 80 feet tall are California sycamore (Platanus racemosa, hardy in U.S. Department of Agriculture plant hardiness zones 7 through 10) and Fremont cottonwood (Populus fremontii, USDA zones 3 through 9). California sycamore has year-round appeal with its multicolored peeling bark and statuesque growing addiction. Large, lobed leaves cast good shade. Fremont cottonwood trees are either male or female, and females produce cottony seeds. Both species need ample watering after planting to get down the roots to the existing water table, which is vital for their ultimate success. Fremont cottonwood is a good tree to plant along river banks, since it grows quickly to soften the soil and then furnishes a more permeable habitat to build other riparian plants. It provides cavities for nest and wildlife sites for hawks and eagles.
Medium-Sized Trees
Medium-sized trees which grow nicely along river banks, black willow (Salix nigra, USDA zones 2 through 8) and also white alder (Alnus rhombifolia, USDA zones 8 through 11) both need root access to the river’s water table Black willow grows 30 to 65 feet tall and also white alder from 50 to 75 feet high. Both tolerate constantly moist soil. Black willow has extensive root systems — considerably larger compared to the icy plant components — that withstand soil erosion and flooding. White alder is among the very best index species of permanent water in native habitats.
Little Trees
Some shorter trees help slow river flood water and stabilize river banks with their above-ground plant components in addition to their roots. Buttonbush (Cephalanthus occidentalis, USDA zones 5 through 9) is usually 6 to 12 feet tall but can reach 20 feet. Bearing spherical clusters of fragrant, white flowers in spring, it thrives in floods, constantly moist soil and standing water. To get a tree which helps prevent water cutting and that does nicely as the very first tree planted along a river bank, contemplate sandbar willow (Salix interior, USDA zones 2 through 8). Reaching around 20 feet high, it efficiently rises even in just deposited river dirt. These two species often grow as tall, multistemmed shrubs as opposed to small trees.
Trees With Edible Fruit
Hairy blue elderberry (Sambucus nigra subsp. Caerulea, USDA zones 7 through 10) rises to 25 feet tall. Showy, spring clusters of white, fragrant flowers are followed by blue-black grasses which furnish food for wildlife. Plants do well in moist soils but can tolerate drier conditions. Elderberry is often included in recovery riparian plantings to help the threatened valley elderberry long-horned beetle. To supply an edible nut, include northern California walnut (Juglans hindsii, USDA zones 7 through 9) in river bank plantings. The green-hulled fruits ripen in autumn upon trees 30 to 60 feet tall and broad.