Ophiostoma novo-ulmi

species of fungus

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Last updated

July 22, 2026

Quick Summary

Ophiostoma novo-ulmi is a species of fungus that causes Dutch elm disease. This disease is a fungoid killer of elms and certain other trees. It was first identified in the United States in 1930 and has since decimated elm populations in Europe and North America.1

The fungus is spread by bark beetles. Symptoms include wilting, yellowing, and browning of leaves, which may drop early. Affected trees can die within months or take longer, and a discoloration appears in the sapwood. Control measures focus on preventing beetle spread and removing infected wood.1

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Dutch elm disease
…late 1940s, another virulent species, O. novo-ulmi, was described in Europe and the United States, and heavy elm losses continued. This species was introduced to Auckland, New Zealand, in 1989, where it was nearly eradicated with aggressive control measures; the country suffered a major outbreak in 2013 due to a…
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…late 1940s, another virulent species, O. novo-ulmi, was described in Europe and the United States, and heavy elm losses continued. This species was introduced to Auckland, New Zealand, in 1989, where it was nearly eradicated with aggressive control measures; the country suffered a major outbreak in 2013 due to a…
Read More