Skip to main content


Ulmus (elms; family Ulmaceae) A genus of mostly large trees, in which the leaves are asymmetrical at the base, and usually hairy, at least beneath. The hermaphrodite flowers appear in clusters before the leaves. The tiny nutlets have a broad, oval wing that aids wind dispersal, and is notched at the tip. The virulent strain of Dutch elm disease that was introduced about 1968 from N. America into Europe has destroyed most European elm trees, but the roots are not normally killed and many elms are re-establishing themselves from sucker shoots. The disease is caused by a fungus Ophiostoma ulmi) and is apparently always transmitted by the elm-bark beetle (Scolytus). Some eastern Asian elms appear to be immune to this disease. Elm wood is used sometimes for making coffins, and hollowed-out elm stems were formerly used for water pipes, as the wood does not decay readily when waterlogged. There are 18 species, occurring in the northern temperate zone, and in the mountains of the Asian tropics.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Ulmus." A Dictionary of Plant Sciences. . 20 Feb. 2019 <>.

"Ulmus." A Dictionary of Plant Sciences. . (February 20, 2019).

"Ulmus." A Dictionary of Plant Sciences. . Retrieved February 20, 2019 from

Learn more about citation styles

Citation styles gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, cannot guarantee each citation it generates. Therefore, it’s best to use citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

The Chicago Manual of Style

American Psychological Association

  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.