Verticillium Wilt
Verticillium dahliae / Verticillium albo-atrum
Range: Throughout the United States; a soilborne fungus persisting for years in soilSee it on the alert map
Symptoms & signs
- Sudden wilting, yellowing, and browning of foliage on one side or a single branch ('flagging')
- olive-green, brown, or black streaking in the sapwood (revealed by peeling bark on a wilting branch)
- branch dieback
- sometimes scorched leaf margins
- can kill rapidly or cause slow, chronic decline
Treatment & management
- No cure — manage culturally
- Prune out dead wood and support vigor with deep watering and balanced (low-nitrogen) fertilization
- vigorous trees can wall off and survive infections
- Do not replant susceptible species in known-infected soil
- choose resistant trees
- Avoid root wounding
- Confirm by lab culture, as it mimics other wilts
Host species
Sugar MapleAcer saccharumRed MapleAcer rubrumSilver MapleAcer saccharinumNorway MapleAcer platanoidesEastern RedbudCercis canadensisSouthern MagnoliaMagnolia grandifloraBigleaf MapleAcer macrophyllumSassafrasSassafras albidumNorthern CatalpaCatalpa speciosaBoxelderAcer negundoJapanese MapleAcer palmatumTree of HeavenAilanthus altissimaSaucer MagnoliaMagnolia × soulangeanaFreeman MapleAcer × freemaniiPaperbark MapleAcer griseumSweetbay MagnoliaMagnolia virginianaAmerican YellowwoodCladrastis kentukeaChinese PistachePistacia chinensisHedge MapleAcer campestreAmur MapleAcer ginnalaCucumbertree MagnoliaMagnolia acuminata
Common questions
Why did one side of my maple suddenly wilt and die?
One-sided or single-branch wilting with dark streaking under the bark is the hallmark of verticillium wilt, a soilborne fungus that plugs the water-conducting vessels. A lab culture confirms it.
Can I save a tree with verticillium wilt?
Sometimes. There is no chemical cure, but keeping the tree vigorous with water and modest fertilization helps it compartmentalize the fungus. Prune out dead wood and avoid replanting susceptible species in that soil.
Related diseases
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