the genus Fraxinus groups around 50 species of trees, or more rarely shrubs, originating in the northern hemisphere. Fraxinus excelsior is native to Europe and Asia; the foliage is wide and round, the stem is slender and usually not very branched, the bark is gray, smooth in young specimens, it tends to become wrinkled and fissured with the passage of time; this tree reaches 30-40 m in height, and in the first years it has a very rapid growth. It has unpaired-pinnate leaves, consisting of 7-9 sessile, oval leaflets, with serrated margins, are dark green, pubescent on the underside; in spring, before the appearance of the leaves, it produces axillary inflorescences, of a purple color. In summer the ash produces fruits consisting of a single seed, endowed with long wings (samara).
The specimens of Fraxinus excelsior grow without problems in any soil, preferring the rich, well-drained and very deep soils, since the root system of the ash trees widens a lot and goes very deep.The ash trees can be planted even in places with poor drainage and in very wet soils, it can also adapt to the more mountainous ones, even if its ideal soil is that of a clayey type. It does not tolerate too compact and dry soils.Watering
The specimens belonging to the Fraxinus excelsior variety require the supply of water in a constant manner with regard to the youngest specimens. As regards the latter, it is good to proceed with regular watering during the first 3/4 years of life to ensure their correct development, while the adult specimens can be satisfied with the rains, given that they develop a root system that goes deep and manages to collect the moisture present in the soil.
Even in the presence of strong humidity this plant can withstand without particular problems.
The multiplication of the specimens belonging to this variety occurs by seed, using in the fall the samaras just fallen from the tree; seedlings must be left outdoors, as seeds need a cold period to germinate. If desired, the seeds can be kept in the refrigerator and sown the following year; however, remember that ash seeds often germinate two years after falling from the plant, and can remain dormant for many years.
Ash - Fraxinus excelsior: Pests and diseases
Ash trees are quite rustic and resistant but can be affected by a fungus, called polypore, which penetrates the bark and causes dangerous rots. Another problem that can arise is that related to the attack by the little family, which causes radical rot that can quickly lead to the death of the plant.