Definition

Noun: * A species of fungus (Ceratostomella ulmi, now more commonly classified as Ophiostoma ulmi or Ophiostoma novo-ulmi) that is the pathogenic agent causing Dutch elm disease. It is a sac fungus (ascomycete) that invades and blocks the water-conducting vessels of elm trees.

Usage Notes

• This is a highly specific scientific term (a taxonomic binomial name) used primarily in botany, plant pathology, and forestry.
• The name is often seen in its modern taxonomic classifications, or , but the historical name Ceratostomella ulmi remains in use, especially in older literature.
• It is used as a singular noun to refer to the fungal species itself.

Examples

• The spread of Ceratostomella ulmi across North America devastated native elm populations.
• Researchers studied the life cycle of Ceratostomella ulmi to develop control methods.
• Dutch elm disease is caused by the fungus Ceratostomella ulmi.

Advanced Usage

• The term is used in formal scientific writing, research papers, and technical reports on plant diseases.
• It can be used attributively (like an adjective) to modify other nouns, e.g., "Ceratostomella ulmi spores," "Ceratostomella ulmi infection."

Variants and Related Words

• Dutch elm disease fungus: A common descriptive name for the pathogen.
• Ophiostoma ulmi: The modern, more accepted taxonomic name for the same or a closely related species complex.
• Ophiostoma novo-ulmi: The name for a more aggressive subspecies responsible for the later pandemic.
• Ascomycete: The broader class of fungi to which it belongs.

Synonyms

• Dutch elm disease pathogen
• Elm wilt fungus (less precise)

Related Phrases/Idioms

• Carrier of Ceratostomella ulmi: Often refers to the bark beetles (e.g., spp.) that transport the fungal spores.
• Ceratostomella ulmi infestation: Describes an active, widespread infection in an area.

Noun

1. fungus causing Dutch elm disease