oak wilt

American  

noun

Plant Pathology.

1. a disease of oaks, characterized by wilting and discoloration of the leaves and defoliation, usually starting at and spreading from the top of the tree and the ends of the branches, caused by a fungus, Chalara quercina.

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Etymology

Origin of oak wilt

An Americanism dating back to 1940–45

Example Sentences

The cost for treating oak wilt, or any tree disease that requires a fungicide injection, depends on the tree’s diameter at breast height, or DBH.

From The Wall Street Journal • Feb. 4, 2026

Leaf blister, sooty mold, oak wilt, leaf scorch: Been there, done that.

From "Wishtree" by Katherine Applegate

This is done in anticipation of oak wilt, which has not yet made its appearance here.

From Northern Nut Growers Association Report of the Proceedings at the 44th Annual Meeting Rochester, N.Y. August 31 and September 1, 1953 by Northern Nut Growers Association

In the late summer of 1951 clearly visible mycelial mats of the oak wilt fungus were found in Illinois under the loose bark of wilt-killed trees.

From Northern Nut Growers Association Report of the Proceedings at the 43rd Annual Meeting Rockport, Indiana, August 25, 26 and 27, 1952 by Northern Nut Growers Association

The oak wilt is a serious threat to the chestnut orchards.

From Northern Nut Growers Association Report of the Proceedings at the 43rd Annual Meeting Rockport, Indiana, August 25, 26 and 27, 1952 by Northern Nut Growers Association