Phytophthora crown and spear rot—Phytophthora spp.
Phytophthora spear rot is characterized by soft, water-soaked lesions on shoots near the soil line. The
lesions elongate rapidly and become light brown. As the lesion collapses and shrivels, the affected side
of the spear becomes flattened, and the shoot becomes extremely curved and may even collapse. Infected
crowns have yellow orange colored tissue. The tissue may appear waterlogged and fibrous.
Crown and spear rot is most common in wet years. Avoid prolonged saturation of the soil and provide good
drainage. Irrigate only as much and only as often as necessary. Plant in Phytophthora -free soil
and use disease-free transplants.
For more information, see the Phytophthora
Root and Crown Rot Pest Note.