Verticillium wilt—Verticillium spp.
Verticillium wilt is a fungal disease that affects the plant's vascular system. It causes the foliage to turn
faded green, yellow, or brown, and sometimes wilt in scattered portions of the canopy or on scattered branches.
Shoots and branches wilt and die, often beginning on one side of the plant, and occasionally entire plants
die. Peeling back the bark on newly infected branches may reveal dark stains following the grain on infected
wood. Many trees are affected, but common hosts include ash, camphor, Chinese pistache, fuchsia, hebe, maple,
olive, pepper tree, pistachio, and rose. A few hosts such as olive exhibit little or no vascular discoloration;
this discoloration is a common field diagnosis symptom for most other woody plants infected by Verticillium
wilt.
Solutions
Keep plants vigorous by providing trees with proper irrigation,
fertilizer, and other appropriate care to
promote new growth and increase their chance for survival. Chronic branch dieback may develop in surviving
trees; prune out any dead wood. Regularly inspect for possible hazards; affected trees may need to be removed.
Where Verticillium wilt has been a problem, plant only resistant
species. Soil
solarization before planting
may be effective.
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 Brown,
dead foliage of Verticillium wilt
Damage to vascular tissue
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