Ulmus

American elm has the largest range of any of the six elm species growing in North America, covering the whole of the eastern parts of the continent west to the Rocky Mountains, but omitting the mountainous areas, high plateaus and the coldest conifer zone. It thrives best in moist valleys and flood meadows, but is quite happy when planted on drier soils.

Resembling the native European elm (U. laevis) in appearance, the American can grow to over 30 metres in the wild. Its characteristic broad, funnel-shaped crown creates a pleasant, cool shade. The oval, smooth leaves turn early in autumn to a golden yellow. The fruit is again similar to that of the native European elm, an almost circular samara with the nutlet surrounded by a broad wing, ripening in mid-summer.

The American elm is an extremely popular park tree in its native range, both fast-growing and attractive in shape. It has long been grown in Finland but remains rare. It is one of the most successful of the species in the Mustila Ulsike project.

The strong-growing Russian elm, despite the common name, is also native to Finland though it is seldom planted and little known nowadays. In the province of Häme it is a typical species of the shores of Lake Vanajavesi, in rich forest soils achieving a diameter of over a metre, given a few centuries. In the past the leathery bark was used where tough bindings were needed, and the wood itself for wooden harness bows.

On young trees the branches are slender but it eventually grows a broad mounded crown, and the trunk is knobbly. It bears clusters of red-brown flowers before coming into leaf; at its best looks as if covered in a red veil.

In its early years the Russian elm is faster-growing than the Scotch or wych elm (U. glabra). The leaves of mature trees are smooth on the upper surface, whereas those of the wych elm are rough like sandpaper. The seeds, which ripen not later than Midsummer, are round nutlets surrounded by a feathery-edged papery wing about 1 cm across.

The Russian elms at Mustila are handsome old trees growing in rich soil near houses and old ruins. A small plantation can be seen at Nokkala. In Finland there has as yet been no sign of damage by Dutch elm disease (Ophiostoma ulmi), which has destroyed vast numbers of elms in warmer climates over recent decades. Russian elm is said to be fairly resistant to this disease.

The naturally very variable Japanese elm is one of the key species in the fight against Dutch elm disease (Ophiostoma ulmi), which has destroyed a large part of the elm populations of central and western Europe, as well as those of North America. Species from Asia seem to have the best resistance.

The Japanese elm can grow in the wild to 30 metres, with a broad crown, but there are also shrubby forms. The leaves are 8-12 cm, and the branches of some provenances have corky wings which make them attractive even in winter.

Mustila’s Japanese elms have grown since the 1990s from seed obtained from Canada. They have grown slowly and are literally being left in the shade by the other elm species on the banks of the pool at the foot of Atsalearinne (Azalea Slope).