Vascular Wilts

Vascular Wilts

Oak Wilt

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Leaf symptoms

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Vascular discoloration in red oak branch is at the outer xylem.

oak wilt discoloration

Vascular discoloration in white oaks can occur within the xylem since white oaks may survive for some time after infection.

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Crack in bark of red oak caused by mycelial mat of the oak wilt fungus.

oak wilt mats

The fungus causing oak wilt produces fungal mats under the bark. These produce pressure to break open the bark.

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Sap feeding beetles that vector oak wilt.

endoconidia

Endoconidia of Bretziella (Ceratocystis) fagacearum. a= conidia, b= conidiophore

endoconidia

Endoconidia of Bretziella (Ceratocystis) fagacearum.