Introduction
Often planted for its fast growth and usefulness as a short-lived screen or windbreak, Lombardy Poplar forms a slender column of many short, upward-pointing branches and can reach 40 to 60 feet in height with a spread of only 10 to 12 feet. But canker disease almost always infects the tree by the time the tree is 10 to 15 years old so trees are rarely seen larger than about 30 feet tall by five feet wide. The triangular to diamond-shaped, 2 to 3.5-inch-long by 1.5 to 3-inch-wide deciduous leaves are bright green on both sides throughout the year, turning a blazing golden yellow in fall before dropping. The small, inconspicuous flowers appear in spring. The bark is grey/green on young trees and new growth, but becomes black, thickened, and furrowed on older, larger trunks.
Credit: Ed Gilman
General Information
Scientific name: Populus nigra
Pronunciation: POP-yoo-lus NYE-gruh
Common name(s): Lombardy Poplar
Family: Salicaceae
USDA hardiness zones: 3A through 9A (Fig. 2)
Origin: not native to North America
Invasive potential: little invasive potential
Uses: reclamation
Availability: somewhat available, may have to go out of the region to find the tree
Description
Height: 40 to 50 feet
Spread: 10 to 12 feet
Crown uniformity: symmetrical
Crown shape: columnar
Crown density: moderate
Growth rate: fast
Texture: fine
Foliage
Leaf arrangement: alternate (Fig. 3)
Leaf type: simple
Leaf margin: crenate, serrate
Leaf shape: deltoid, ovate
Leaf venation: pinnate
Leaf type and persistence: deciduous
Leaf blade length: 2 to 4 inches
Leaf color: green
Fall color: yellow
Fall characteristic: showy
Flower
Flower color: red
Flower characteristics: not showy
Fruit
Fruit shape: no fruit
Fruit length: no fruit
Fruit covering: no fruit
Fruit color: no fruit
Fruit characteristics: does not attract wildlife; no fruit; fruit/leaves not a litter problem
Trunk and Branches
Trunk/bark/branches: branches don't droop; not showy; typically one trunk; thorns
Pruning requirement: little required
Breakage: susceptible to breakage
Current year twig color: brown
Current year twig thickness: thin
Wood specific gravity: unknown
Culture
Light requirement: full sun
Soil tolerances: clay; sand; loam; alkaline; acidic; occasionally wet; well-drained
Drought tolerance: high
Aerosol salt tolerance: moderate
Other
Roots: not a problem
Winter interest: no
Outstanding tree: no
Ozone sensitivity: unknown
Verticillium wilt susceptibility: unknown
Pest resistance: sensitive to pests/diseases
Use and Management
If planted, Lombardy Poplar should be grown in full sun on well-drained, acid or alkaline soil. It tolerates wet soil well but also performs in drought, losing leaves early in very dry summers. Multiple suckers often appear at the base of trees and occasionally on roots far from the tree, and the roots are considered invasive. Also, the trees are, unfortunately, very susceptible to stem canker disease which usually limits their life to only 10 or 15-years. Plant other narrow-crowned trees including `Fastigiate' European Hornbeam, Armstrong Maple, `Fastigiata' Alder, Fastigiate English Oak, Leyland Cypress, and others instead of this tree.
Propagation is by cuttings since Lombardy Poplar is a male clone.
Pests
No pests are of major concern.
Diseases
Stem canker disease is so devastating that this tree is usually not included on any recommended tree lists, with the exception of a reclamation site. Choose from the many other available columnar or upright screening trees for a more durable planting.
