Aphids
Aphidoidea (various species)
Range: Throughout the United States and Canada on a vast range of host plantsSee it on the alert map
Symptoms & signs
- Clusters of small soft-bodied insects on new shoots and leaf undersides
- curled, puckered, yellowing, or distorted new growth
- sticky honeydew coating leaves and surfaces below, followed by black sooty mold
- ants 'farming' the aphids
- swarms of wasps and flies drawn to the honeydew
Treatment & management
- Often controlled by natural predators (lady beetles, lacewings, parasitic wasps) — preserve them
- Hose off light infestations with water
- Insecticidal soap or horticultural oil for moderate cases
- systemic imidacloprid for persistent honeydew problems on high-value trees
- Avoid excess nitrogen, which fuels soft, aphid-prone growth
Host species
Silver MapleAcer saccharinumEastern White PinePinus strobusTulip Poplar (Yellow Poplar)Liriodendron tulipiferaRiver BirchBetula nigraHoneylocustGleditsia triacanthosCrapemyrtleLagerstroemia indicaCommon HackberryCeltis occidentalisBlack CherryPrunus serotinaBoxelderAcer negundoJapanese MapleAcer palmatumFreeman MapleAcer × freemaniiPaperbark MapleAcer griseumYellow BirchBetula alleghaniensisSitka SprucePicea sitchensisJapanese ZelkovaZelkova serrataHedge MapleAcer campestreAmur MapleAcer ginnalaTrident MapleAcer buergerianumSweet Birch (Black Birch)Betula lentaEnglish Walnut (Persian Walnut)Juglans regiaEuropean BeechFagus sylvaticaBigtooth AspenPopulus grandidentataBlack WillowSalix nigraYoshino CherryPrunus × yedoensisGoldenrain TreeKoelreuteria paniculataLittleleaf LindenTilia cordataRed AlderAlnus rubraVine MapleAcer circinatum
Common questions
Why is everything under my tree sticky and black?
Aphids (or related sap-suckers) excrete sugary honeydew that drips onto cars, decks, and lower leaves, where black sooty mold then grows. Managing the aphids stops both the stickiness and the mold.
Do I need to spray for aphids?
Usually not — lady beetles and other predators often crash aphid populations on their own. Reserve insecticidal soap, oil, or systemics for persistent, heavy infestations on valued trees.
Related pests
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