Lombardy poplar

LC - Least Concern

NNA - Not applicable

SNA - Not applicable

not listed

Lombardy poplar is a non-native, cultivated variety. It is a deciduous hardwood tree. It rises on a single stem from a shallow, wide-spreading root system. It is fast growing and short lived, commonly lasting only 30 to 50 years. The short lifespan is due to its susceptibility in humid environments to fungal diseases which cause cankers. It does not escape cultivation but may spread vegetatively. Mature trees are up to 60′ tall.

The trunk is slender with many branches. The crown is columnar and very narrow. It begins nearly at the base of the trunk and usually spreads no more than 10′ to 15′. The top of the crown is often dead. The branches are clustered, erect, and held close to the trunk.

The bark on young trees is smooth and grayish-green. It does not peel like paper birch. As it ages it becomes thick and gray, with rough, irregular furrows, at least near the base of the tree.

The current-season twigs are moderate to stout, swollen at the leaf nodes, yellowish-brown, and shiny. They turn dull gray and rough in the second year.

The buds are yellow to yellowish-brown and resinous when squeezed. They are less than ½″ long, cone-shaped, slender, tapering, and pointed. They are covered with 3 or 4 visible bud scales. The lower scales are densely hairy. The upper scales are hairless and shiny.

The leaves are deciduous, alternate, 2″ to 4″ long, and not lobed or divided (simple). They are hairy when young, soon becoming hairless. The upper surface is dark green with a definite translucent border. The lower surface is paler green. The margins are finely and shallowly toothed. The teeth are no more than about 1 ⁄32″ deep and are not or only slightly curved inward at the tip (this may be visible only with a hand lens). Leaf blades on short shoots are rhomboid egg-shaped and more or less wedge-shaped at the base. Leaf blades on long shoots are broadly triangular egg-shaped, mostly wider than long, abruptly pointed at the tip, and straight across at the base. The leaf stalk is ⅓″ to ⅔″ as long as the leaf blade and is distinctly flattened perpendicular to the plane of the blade. There are no visible warty glands at the base of the leaf blade where it attaches to the stalk.

Male and female flowers are borne on separate plants. However, all individuals of this cultivar trace back to a single male clone, hence all individual plants are male. The flowers appear before the leaves in early spring. They are borne in 2″ to 3″ long, crowded, pendulous, reddish- to yellowish-green catkins on 2nd year branchlets.

This cultivar does not produce fruit.

Up to 60′

There is no state champion of non-native trees.

Reddish or greenish-yellow

Dry. Old homesteads.

Early April to early mid-May

Pemphigus populicaulis (no common name) is an aphid that causes a gall at the junction of leaf blade and petiole. The opening in the gall is a slit running parallel to the direction of the petiole.

Sources

2, 3, 4, 5, 7, 8, 22, 28, 29, 30.

Species native to Europe, Asia, and northern Africa. Cultivar selected in northern Italy, widely cultivated, rarely escaped.

Uncommon in Minnesota outside of cultivation.