The American Elm cultivar ''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 a lake located in Livingston County, New York. Conesus Lake is the westernmost of New York's eleven Finger Lakes. It is located off Interstate 390 about south of Interstate 90. Description Conesus Lake is long, with a maximum ...

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

, 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 Rehder is a German surname. Notable people with this surname include the following: * Alfred Rehder (1863–1949), German-American botanist and Harvard professor * Elke Rehder (born 1953), German artist * Harald Alfred Rehder (1907–1996), Ameri ...

(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 Elm yellows is a plant disease of elm trees that is spread by leafhoppers or by root grafts."Elm Yellows." Elmcare.Com. 19 Mar. 2008 . Elm yellows, also known as elm phloem necrosis, is very aggressive, with no known cure. Elm yellows occurs in the ...

; it is also moderately preferred for feeding and reproduction by the adult Elm Leaf Beetle '' Xanthogaleruca luteola'', and highly preferred for feeding by the Japanese Beetle ''

Popillia japonica The Japanese beetle (''Popillia japonica'') is a species of scarab beetle. The adult measures in length and in width, has iridescent copper-colored elytra and a green thorax and head. It is not very destructive in Japan (where it is control ...

'' 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. theobromae'' and ''V. tricorpu ...

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

Cultivation

'A specimen of 'Columnaris' was present in

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

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

Accessions

;North America * Morton Arboretum, Illinois, 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