When picking tree species to plant this spring, be aware of some common invasive trees that may still be available for purchase. Buckthorn and Siberian Elm are invasive trees that many are aware of; however, be aware of the following species that also are invasive, and avoid planting them.
- Norway Maple (Acer platanoides) is a large deciduous tree native to Europe and Western Asia, growing up to 6o feet in height. It can tolerate many different growing environments, and has been a popular landscape tree due to its hardiness. The Norway maple has shallow roots and shade out many different species of native understory plants. They also produce a large number of winged seeds that can spread long distances. Norway maples have a prominent five-lobed leaf.
- Callery (Bradford) Pear (Pyrus calleryana) is a fruit tree native to Asia. It was originally introduced as a rootstock for domesticated pears in the early 1900s. This tree has invasive traits that enable it to spread aggressively when it hybridizes. Leaves are alternate, simple and shiny. It can grow up to 60 feet in height.
- Tartarian Maple (Acer tataricum) Native to eastern Europe and western Asia, this species has escaped gardens and has become aggressive in forests, forest edges, and disturbed habitats. Leaves are simple, and can be lobed or unlobed. Tartarian Maple grows and a shrub or small tree, up to 30 feet tall.
- Amur Maple (Acer ginnala) Amur maple is native to northern China, Japan, and Manchuria. It was widely sold and planted in Minnesota as an ornamental landscape tree, and used as a windbreak, hedge, and screen planting. It grows to 20 feet tall with bright red fall foliage. Leave are opposite and have toothed, 3-lobed leaves.
- Amur Cork Tree (Phellodendron amurense) Amur corketree was introduced in the 1850’s as an ornamental landscape tree. It is native to northern China, Japan, and Manchuria. It has somewhat corky bark, which gives it its name. Leaves are opposite and compound. Leaflets are dark green on top and light green on the underside, and smell like turpentine when curshed. It is highly adaptable, and female plants produce many seeds that germinate rapidly and outcompete native understory tree species.
For more information: MN Department of Natural Resources or email Krista Spreiter, Natural Resources Technician.