The

American Elm ''Ulmus americana'', generally known as the American elm or, less commonly, as the white elm or water elm, is a species of elm native to eastern North America. The trees can live for several hundred years. It is a very hardy species that can ...

cultivar A cultivar is a kind of Horticulture, cultivated plant that people have selected for desired phenotypic trait, traits and which retains those traits when Plant propagation, propagated. Methods used to propagate cultivars include division, root a ...

''Ulmus americana'' 'Columnaris' was propagated by R. E. Horsey of the Rochester N.Y. Parks Department from a tree found by Mr John Dunbar at

Conesus Lake Conesus Lake is located in Livingston County, New York. Conesus Lake is one of New York's twelve Finger Lakes. It is located off Interstate 390 about south of Interstate 90. Description Conesus Lake is long, with a maximum depth of . I ...

New York New York most commonly refers to: * New York (state), a state in the northeastern United States * New York City, the most populous city in the United States, located in the state of New York New York may also refer to: Places United Kingdom * ...

, in 1911, and originally described as a ''forma'', ''Ulmus americana'' L. f. ''columnaris'', f. ''nov.'' Rehder (1922).'Ulmus americana L. f. columnaris, f. nov.', ''Journal of the Arnold Arboretum'', Vol.3, p.42; Cambridge, Mass. 1922
/ref> It was the earliest of a number of compact, columnar American elm cultivars, to be followed by 'Ascendens' and 'Augustine Ascendening'.

Description

As implied by its name, the tree has a fastigiate, columnar form, of almost equal width from the base to a top which is rather flat in appearance. "The leaves differ from those of the common form," wrote Rehder (1922), "in being rather broad, measuring up to 7.5 cm. in width, very sharply and deeply doubly serrate, scabrous above, pilose on the veins and veinlets beneath and very unequal at the base; the petioles are very short, not exceeding 3 mm. in length; the young branchlets are pubescent."Leaves of 'Columnaris', bioportal.naturalis.nl, specimen L.1590846
/ref>

Pests and diseases

No specific information available, but the species as a whole is highly susceptible to Dutch Elm Disease and Elm Yellows; it is also moderately preferred for feeding and reproduction by the adult Elm Leaf Beetle ''

Xanthogaleruca luteola ''Xanthogaleruca luteola'', commonly known as the elm-leaf beetle, is a beetle species in the family Chrysomelidae that is native to Europe but invasive in other parts of the world.http://cisr.ucr.edu/elm_leaf_beetle.html - Center for Invasive ...

'', and highly preferred for feeding by the Japanese Beetle ''

Popillia japonica The Japanese beetle (''Popillia japonica'') is a species of scarab beetle. Due to the presence of natural predators, the Japanese beetle is not considered a pest in its native Japan, but in North America and some regions of Europe, it is a no ...

'' in the United States. ''U. americana'' is also the most susceptible of all the elms to

verticillium wilt Verticillium wilt is a wilt disease affecting over 350 species of eudicot plants. It is caused by six species of '' Verticillium'' fungi: ''V. dahliae'', ''V. albo-atrum'', ''V. longisporum'', ''V. nubilum'', ''V. theobr ...

.Pegg, G. F. & Brady, B. L. (2002). ''Verticillium Wilts''. CABI Publishing.

Cultivation

'A specimen of 'Columnaris' was present in

Arnold Arboretum The Arnold Arboretum is a botanical research institution and free public park affiliated with Harvard University and located in the Jamaica Plain and Roslindale, Massachusetts, Roslindale neighborhoods of Boston. Established in 1872, it is the ...

. The tree is not known to have been cultivated beyond the United States, and is no longer in commerce.

Accessions

;North America *

Morton Arboretum The Morton Arboretum, in Lisle, Illinois, United States, is a public garden and outdoor museum with a library, herbarium, and program in tree research including the Center for Tree Science. Its grounds, covering 1,700 acres (6.9 square kilometre ...

Illinois Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. It borders on Lake Michigan to its northeast, the Mississippi River to its west, and the Wabash River, Wabash and Ohio River, Ohio rivers to its ...

, US. Specimen in the Columnar Tree Section reputed to be "in good health" in the autumn of 2006. Acc. no. 1041–41, (graft).

References

External links

*http://www.bgci.org/plant_search.php?action=Find&ftrGenus=Ulmus&ftrRedList=&ftrSpecies=&ftrRedList1997=&ftrEpithet=&ftrCWR=&x=41&y=19NB. Botanic Gardens Conservation International register *http://redwood.mortonarb.org/PageBuilder?cid=2&qid=13 Morton Arboretum catalogue {{Elm species, varieties, hybrids, hybrid cultivars and species cultivars , state=collapsed American elm cultivar Ulmus articles with images Ulmus