COMMON NAME

White poplar
Silver poplar


FULL SCIENTIFIC NAME

Populus alba L.


FAMILY NAME COMMON

Willow family


FAMILY SCIENTIFIC NAME

Populus alba


IMAGES


Leaf aspects

Branch with flowers

Close-up of inflorescences

Habit

Lower leaf surface

Upper leaf surface

Habitat

Bark Texture

Clonal Runners

NOMENCLATURE/SYNONYMS

Synonyms: None


DESCRIPTION

Botanical Glossary

Populus alba is a deciduous tree that can grow up to 18-30 m (60-100 ft.) in height and 12-18 m (40-60 ft.) in spread. A very large tree could have a trunk diameter up to 1.8 m (6 ft.). The bark is very white and smooth when the tree is young. With age, the bark becomes darker and more furrowed. The terminal bud, young stems, and young leaves of the tree are densely tomentose, giving them a white appearance. As the leaves age they become dark green and glabrous above, while the lower leaf surfaces remain white and tomentose. The leaves are arranged alternately. Leaves on the longer shoots are palmately, 3-7 lobed. The shorter shoots have leaves that are ovate in shape with irregularly dentate margins. The apex of the leaf is acute, while the base is truncate or subcordate. The leaves measure 6-10 cm (2.5-4 in.) in length. This species is dioecious, having separate male and female trees. The yellowish catkins containing the male or female flowers measure about 5 cm (2 in.) long, with the staminate catkins sometimes being longer. The catkins appear on the tree in early spring before the leaves have emerged, usually in late March or early April. The fruit are small, measuring 5-7.5 mm (0.2-0.3 in.). They are dark brown and dry. Attached to the seeds are white hairs that allow for transport by wind. The seeds are usually detached from the tree by late spring. Page References Bailey 321, Fernald 522, Gleason & Cronquist 167, Holmgren 152, Magee & Ahles 395. See reference section below for full citations.


SIMILAR SPECIES

Populus grandidentata Michx. (bigtooth aspen)
Populus tremuloides Michx. quaking aspen)
Populus hybrids Populus grandidentata and P. tremuloides both have flat petioles, while Populus alba has round petioles. While the twigs and terminal buds of P. grandidentata and P. tremuloides can be somewhat hairy, those of P. alba are tomentose.


REPRODUCTIVE/DISPERSAL MECHANISMS

Populus alba can move long distances by means of it wind-dispersed seeds. However, the seeds are not highly viable, and these plants spread vegetatively via suckers.


DISTRIBUTION

Populus alba is native to Europe. Its range extends from Spain in the west, to Italy in the south, Germany in the north and the European part of Russia in the east. It is present in all of the United States, with the exception of Arizona, Alaska and Hawaii. This species has been reported from all New England states.


HISTORY OF INTRODUCTION IN NEW ENGLAND

Populus alba was introduced into the United States in 1784 from Europe, where it has long been cultivated as a landscape and street tree both in rural and urban areas. From these early introductions it has naturalized throughout the country.


HABITATS IN NEW ENGLAND

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.


THREATS

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 LINKS

Plant Conservation Alliance
Fact sheet including management information


DOCUMENTATION NEEDS

Documentation required: A specific photograph or mounted snippet of the leaves showing the white lower surface.
Best time for documentation: Summer, fall.


ADDITIONAL INFORMATION

Integrated Taxonomic Information System
Taxonomic information

The PLANTS database
General information and map

Plant Conservation Alliance
Fact sheet including control information

University of Connecticut Plants Database
Descriptive information and photographs

Virginia Tech Dendrology
Description and photographs


REFERENCES

Bailey, L.H.  1949.  Manual of Cultivated Plants.  Macmillan, New York.

Britton, N.L. and A. Brown.  1970.  An Illustrated Flora of the Northeastern United States vol. 1.  Dover Publications Inc., New York. 

Dirr, M.A. 1998.  Manual of Woody Landscape Plants.  5th ed.  Stipes Publishing, Champaign, Illinois.

Fernald, M.L. 1950. Gray's Manual of Botany 8th ed. American Book Co., Boston.

Glass, W. 1996. Populus alba, p.39. In Randall, J.M. and J. Marinelli. [eds.].  Invasive Plants: Weeds of the Global Garden. Brooklyn Botanic Garden Inc., New York.

Gleason, H.A. and A.C. Cronquist.  1991.  Manual of Vascular Plants of the Northeastern United States and Adjacent Canada. 2nd ed.  New York Botanical Garden, Bronx, New York.

Holmgren, N.H. 1998. Illustrated Companion to Gleason and Cronquist's Manual.  New York Botanical Garden, Bronx, New York.

Magee, D.W and H.E. Ahles. 1999.  Flora of the Northeast. University of Massachusetts Press, Amherst.

Randall, J. and J. Marinelli, eds. 1996. Invasive plants: Weeds of the Global Garden. Brooklyn Botanical Garden, Brooklyn, New York.

USDA, NRCS.  2001.  The PLANTS Database, Version 3.1. (http://plants.usda.gov).  National Plant Data Center, Baton Rouge, LA 70874-4490 USA.