Ulmus × hollandica Mill. , often known simply as Dutch elm, is a natural hybrid between Wych elm Ulmus glabra and field elm Ulmus minor which commonly occurs across Europe wherever the ranges of the parent species overlap. In England, according to the field-studies of R. H. Richens, "The largest area [of hybridization] is a band extending across Essex from the Hertfordshire border to southern Suffolk. The next largest is in northern Bedfordshire and adjoining parts of Northamptonshire. Comparable zones occur in Picardy and Cotentin in northern France". Crosses between U. × hollandica and either of the parent species are also classified as U. × hollandica. Ulmus × hollandica hybrids, natural and artificial, have been widely planted elsewhere. The botanical name hollandica was first used for an elm variety by Plukenet in 1697 in describing a cultivar of this group now called 'Major'. Description In form and foliage, the trees are broadly intermediate between the two species. F1 hybrids between wych and field elm are fully fertile, but produce widely variant progeny. Many also inherit the suckering habit of their field elm parent. Both Richens and Rackham noted that examples in the East Anglian hybridization zone were sometimes pendulous in form. Pests and diseases Some examples of the hybrid possess a moderate resistance to Dutch elm disease. Cultivation The hybrid has been introduced to North America and Australasia. Notable trees The great elm in The Grove of Magdalen College, Oxford, photographed by Henry Taunt in 1900, long believed to be a wych elm before being identified by Elwes as a 'Vegeta'-type hybrid, was for a time the largest elm known in Britain before it was blown down in 1911. It measured 44 m tall, its trunk at breast height being 2.6 m in diameter, and comprised an estimated of timber, making it the largest tree of any kind in Britain and possibly the largest north of the Alps. However, as Elwes pointed out, its calculated age would place its planting in the late 17th or early 18th century, long before the introduction of the Huntingdon elm, making the tree in question more likely to be a Chichester elm. A second tree nearby, described by Elwes as "similar in habit and foliage" (see 'External links') and tall by in girth in 1912, was confirmed by Nellie Bancroft in a Gardener's Chronicle article in 1934 as a 'Vegeta'-type hybrid; it was propagated