Fraxinus excelsior Aarsee - Common Ash

Fraxinus excelsior 'Aarsee' is a botanical oddity, a variety of Common Ash that will astonish many. This small tree with slow to moderate growth is remarkable for its compound foliage with very small leaflets. On the current year's growth, the leaves can even be reduced to just the veins, giving the plant an extremely bizarre, vaguely ghostly appearance. More curious than truly beautiful, it will mostly appeal to plant enthusiasts looking for something out of the ordinary. Easy to cultivate in most moist soils, it can be planted alone or in a bed with other unique plants.

The Ash belongs to the Olive family, which includes many ornamental plants, often fragrant, such as Jasmines (Jasminum) or Lilacs (Syringa), as well as the venerable Olive tree (Olea) from which it gets its name. There are about sixty-five species of Ash, mostly trees and a few shrubs, recognisable (with rare exceptions) by their odd-pinnate leaves (composed of an odd number of leaflets due to the terminal leaflet), generally opposite or sometimes grouped in threes. Fraxinus excelsior is our Common Ash, one of the tallest trees in Europe, reaching heights of up to 30m. Its generally straight trunk has initially grey and smooth bark, which darkens and fissures as it ages. Its compound leaves measure 20 to 30cm in length and have 7 to 13 lanceolate leaflets. The yellow-greenish flowers develop into elliptical samaras measuring 3 to 4cm in length. It is common in forests and along riverbanks and can live for 150 to 200 years.
Fraxinus excelsior 'Aarsee' has a very different appearance from the typical species. It is smaller and will only reach a height of 5 to 10m after 10 to 20 years of cultivation, with a crown width of 5 to 7m. Its growth is slower than the botanical species due to its reduced leaf surface area, resulting in lower photosynthetic activity. However, its moderate growth is still faster than dwarf cultivars. Its branches, initially green at the tips, turn grey as they age. They tend to grow more or less horizontally before straightening upwards, giving the crown a more or less spherical shape, resembling a loose dome.
The foliage appears quite late in spring, as is often the case with Ash trees. The leaves are composed of 5 to 11 leaflets and exhibit various morphologies. On older branch segments, they are relatively "normal," simply slightly smaller than those of the wild species and occasionally slightly deformed. However, on the current year's growth, the leaflets are very narrow, giving the leaves a narrow appearance, and in the most extreme cases, the leaf blade is reduced to just the veins! These shoots often have a crinkled appearance, with slight yellowish discolouration resembling certain virus symptoms. It's a love-it-or-hate-it plant! The inconspicuous flowering has no ornamental value.

The 'Aarsee' Common Ash is a unique plant that will appeal to collectors. This small tree is very hardy (down to -30 °C) and can be integrated into a "bizarretum" composed of other plants with strange silhouettes. Its finely divided foliage provides light shade, which is suitable for plants that prefer partial sun. Plant a Cryptomeria japonica 'Cristata' next to it, a Japanese conifer that forms rooster-like crests of fused young shoots at the ends of its branches, and will compete in strangeness with your Ash tree. The Twisted Hazel (Corylus avellana 'Contorta'), with its winter silhouette characterised by branches that undulate like snakes, will also be a beautiful specimen to incorporate into your scene. Another botanical curiosity, Robinia pseudoacacia 'Twisty Baby', is a small Black Locust tree with a fine and twisted branching pattern that perfectly complements the effect of your plant arrangement.