We all need a break from favourite subjects from time to time.
In addition to that, it may be that for a few intending tree-planters the elm is just not the right way forward at all. If (a) you need nothing less than immunity to the anxiety of elm disease; (b) you need to know what your sapling will look like in 150 years’ time; and (c) you have a very large space to fill with a tree, read on. Read on as well if you are interested in mixed planting. Given the increasing frequency with which tree diseases are now reaching this country, mixed plantings should be the rule.
Various trees have been proposed as suitable replacements for elm. Black poplar was one, on account of its imposing trunk and the fact that it was endangered and needed a conservation boost. However, its crown is not at all elm-like. Another was the South American Nothofagus or Southern Beech, though that genus always brings with it something of the cloud forest rather than the shires.
In reality, the place of the elm in the open countryside has largely been assumed by the oak. It’s just that there aren’t enough oaks to replace the elms, and – wonderful though they are – they’re menaced by too many diseases and pests to be a sound future investment.
On estates and in parks, elm has often been replaced by its old rival in these settings, Common Lime, the hybrid Tilia x vulgaris. That tree has the advantage of reaching a height which compares with elm, but its foliage is pale and the crown is frequently too narrow to be truly imposing.
The Small-Leaved Lime (Tilia cordata), one of the parents of Common Lime, is an excellent replacement for wych elm. In some settings the two can be hard to tell apart at a distance.
The tree which has too often been overlooked is the second of the native lime species, Tilia platyphyllos, the so-called Large-Leaved Lime (its leaves are not in fact especially large). This is the other parent of Common Lime. The photograph below captures its elm-like magnificence. This tree at Tortworth Court in Gloucestershire must be more than 110 foot high.
Here’s another suggestion, not made before as far as I am aware. Carya cordiformis, the Bitternut or Swamp Hickory of eastern North America. It grows to about 100 foot, lives for 200 years, tolerates a wide range of soils, and has a branching pattern more reminiscent of English elm than do the great majority of native trees. Its timber is tough, elastic (and reputed to be among the best for smoking things). It may seem eccentric to propose a tree with large pinnate leaves as a stand-in for a tree with small leaves, but the individual leaflets of the Hickory are not un-elm-like. The crown is lighter in form and colour than that of elm, recalling the native ash. But these days, of course, we need to be considering replacements for the ash as well…..