The woolly elm aphid (Eriosoma americanum) is an aphid native to North America, found where Saskatoon (Amelanchier alnifolia) and American (Ulmus americana) elm trees are established.
The aphid feeds on the Saskatoon elm in late spring through fall, and the American elm during both early spring and late fall.[1]
Symptoms of American elm infestations include curled elm leaves, later accompanied by masses of visible dark areas and cottony masses. As with other aphids, honeydew may be found on infected leaves, excreted by the aphids after feeding on the plant's sap.
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Elm leaf infested with woolly elm aphids in different stages of development The woolly elm aphid (Eriosoma americanum) is an aphid native to North America, found where Saskatoon (Amelanchier alnifolia) and American (Ulmus americana) elm trees are established.
The aphid feeds on the Saskatoon elm in late spring through fall, and the American elm during both early spring and late fall.
Symptoms of American elm infestations include curled elm leaves, later accompanied by masses of visible dark areas and cottony masses. As with other aphids, honeydew may be found on infected leaves, excreted by the aphids after feeding on the plant's sap.
American elm leaves with woolly elm aphid infestation. Curled elm leaves are characteristic of the effects of the aphids, even prior to cottony masses being apparent.
