White poplar

Populus alba

Invader Images

    • White Poplar Bark
      White Poplar Bark
    • White Poplar Infestation
      White Poplar Infestation
    • White Poplar Leaves
      White Poplar Leaves
    • White Poplar Seeds
      White Poplar Seeds

Common Look-alikes

    • Bigtooth Aspen Leaves
      Bigtooth Aspen Leaves
    • Bigtooth Aspen Bark
      Bigtooth Aspen Bark

Identification

Appearance

Populus alba is a tree that can grow 40-80 ft. (12.2-24.4 m) tall and 40-50 ft. (12.2-15.2 m) wide. The bark on young trees is smooth and greenish white becoming gray and wrinkled, as trees age.

Foliage

The leaves resemble maple leaves, but the topside of leaves are shiny, dark green while the underside is bright white and hairy. Leaves are 2-4 in. (5.1-10.2 cm) long.

Flowers

Flowers are inconspicuous and develop in slim, cylindrical flower clusters (catkins) before the leaves develop.

Fruit

Fruit are small, hairy seed pods that are spread by wind.

Biology

This is considered a watch list species

Origin

Native to Europe

Habitat

Agricultural Field, Early Successional Forest, Edge, Floodplain Forest, Open Disturbed Area, Pasture, Roadside, Shrub Wetland, Vacant Lot, Wet Meadow, Yard or Garden. Populus alba prefers areas of disturbance where it can get ample sun. It can tolerate a variety of soils and different levels of pH, as well as a fair amount of salt.

Life cycle

Root suckers arise from adventitious buds on the extensive lateral root system. Large numbers of suckers from a single tree can quickly develop into a dense colony. Suckering can occur naturally or as a result of damage or other disturbance to the parent plant. Mature white poplar trees produce thousands of wind-dispersed seeds that may be carried long distances. However, seed germination of white poplar appears to be very low in the U.S.

Ecological Threat

Populus alba can form large clonal communities that are capable of excluding native species from edge habitats. When attempts are made to cut it back, it vigorously resprouts and spreads even more. Since it is competitive in early successional situations, it can interfere with succession in disturbed habitats. It is a very brittle tree that is easily broken and can cause damage to nearby structures or other trees.

Management Options

Mechanical Control

White poplar can be controlled using a variety of physical and chemical controls. Removal of seedlings and young plants by hand will help prevent further spread or establishment. Plants should be pulled as soon as they are large enough to grasp. The entire root system, or as much of it as possible, should be removed to prevent resprout from fragments. Hand removal of plants is best achieved after a rain, when the soil is loose.

Trees of any size may be felled by cutting at ground level with power or manual saws. Because resprouts are common after cutting, this process may need to be repeated many times until the reserves of the tree are exhausted. Girdling, which kills the tree by severing tissues that conduct water and sugars, also may be effective for large trees, especially if accompanied by application of a systemic herbicide to the cut area. A hatchet or saw is used to make a cut through the bark encircling the base of the tree, approximately six inches above the ground and deep into the bark. Girdling will kill the parent tree but may require follow-up cutting or treatment of sprouts with an herbicide. 

Chemical Control

Chemical control of white poplar seedlings and small trees has been achieved by applying a 2% solution of glyphosate (e.g., Roundup®) or triclopyr (e.g., Garlon® 3) and water plus a 0.5% non-ionic surfactant to the foliage until the leaves are thoroughly wet. Use of low pressure and a coarse spray with large droplet size will reduce spray drift and damage to non-target plants.

**Be careful not to damage or kill nearby native plants when conducting management work. And when using herbicides, always follow the instructions on the label.**

Citations

Photo Credit

5398214, Robert Vidéki, Doronicum Kft., Bugwood.org

5527568, T. Davis Sydnor, The Ohio State University, Bugwood.org

5446810, 5446813, Leslie J. Mehrhoff, University of Connecticut, Bugwood.org

5458751,  Rob Routledge, Sault College, Bugwood.org

5527549, T. Davis Sydnor, The Ohio State University, Bugwood.org

Information Credit 

Go Botany

Invasive Plant Atlas of New England

Plant Conservation Alliance

Bigwood