Ulmus 'Klemmer'

Ulmus × hollandica cultivar
'Klemmer' at Kew, before 1976
Hybrid parentage	U. glabra × U. minor
Cultivar	'Klemmer'
Origin	Belgium

Ulmus × hollandica 'Klemmer', or Flanders Elm, is probably one of a number of hybrids arising from the crossing of Wych Elm (Ulmus glabra) with a variety of Field Elm (Ulmus minor), making it a variety of Ulmus × hollandica. Originating in the Bruges area, it was described by Gillekens in 1891 as l'orme champêtre des Flandres in a paper which noted its local name, klemmer, and its rapid growth in an 1878–91 trial.Kew,Henry (1913), and Krüssmann (1976) listed it as an Ulmus × hollandica cultivar, though Henry noted its "similarity in some respects" to field elm, and Green regarded it as "possibly U. carpinifolia (: minor)".

The name 'Klemmer' derives from the Flemish for 'climber', a reference to the tree's rapid growth and lofty height.Klemmeri, used by the Späth nursery among others, is a misnomer, incorrectly implying a proper noun Klemmer.

Not to be confused with 'Klehmii', a cultivar of Ulmus americana named for Charles Klehm, an Illinois nurseryman.

'Klemmer' is a tall, fast growing tree, with a straight cylindrical stem and ascending branches, initially forming a narrow, conical or pyramidal head which later broadens, and producing numerous root-suckers and some epicormic shoots. The bark, smooth in young trees, is later fissured. The leaves are ovate, up to 7.5 cm (3 in) long (Krüssmann says up to 10 cm) and up to 5.0 cm (2 in) broad, shortly acuminate at the apex, the upper surface dark green, scabrous and glabrescent, the margins slightly crispate. The seed is situated close to the notch of the samara. The timber is reddish in hue, strong but liable to warping. Feneau noted (1902) that young trees were susceptible to frost damage.