Trees & Shrubs – The Ash – A common London tree found in parks and gardens.
The Ash (Fraxinus excelsior)
Fraxinus excelsior — known as the ash, or European ash or common ash to distinguish it from other types of ash — is a species of Fraxinus native to most of Europe.
The second commonest native tree in the UK after oak. Fraxinus excelsior or simply “the ash” as it is normally known in Britain, gained The RHS Royal Horticultural Society AGM Award of Garden Merit. Ash is excellent firewood, being ready to burn while still green.
If ash be brown or ash be green
ash burns fit for a queen!
(Anon – from traditional forestry poem)
It is a large deciduous tree growing to 20–35 m (66–115 ft) (exceptionally to 46 m or 151 ft) tall with a trunk up to 2 m (6.6 ft) (exceptionally to 3.5 m or 11 ft) diameter, with a tall, domed crown. The bark is smooth and pale grey on young trees, becoming thick and vertically fissured on old trees. The shoots are stout, greenish-grey, with jet black buds (which distinguish it from most other ash species, which have grey or brown buds). The leaves are 20–35 cm (7.9–13.8 in) long, pinnate compound, with 7-13 leaflets, the leaflets 3–12 cm (1.2–4.7 in) long and 0.8–3 cm (0.31–1.18 in) broad, sessile on the leaf rachis, and with a serrated margin. The leaves are often among the last to open in spring, and the first to fall in autumn if an early frost strikes; they have no marked autumn colour, often falling dull green. The flowers open before the leaves, the female flowers being somewhat longer than the male flowers; they are dark purple, and without petals, and are wind-pollinated. Both male and female flowers can occur on the same tree, but it is more common to find all male and all female trees; a tree that is all male one year can produce female flowers the next, and similarly a female tree can become male. The fruit is a samara 2.5–4.5 cm (0.98–1.77 in) long and 5–8 mm (0.20–0.31 in) broad, often hanging in bunches through the winter; they are often called ‘ash keys’. If the fruit is gathered and planted when it is still green and not fully ripe, it will germinate straight away, however once the fruit is brown and fully ripe, it will not germinate until 18 months after sowing (i.e. not until two winters have passed).
European Ash rarely exceeds 250 years of age. However there are numerous specimens estimated between 200 and 250 years old and there are a few over 250. The largest is in Clapton Court, England and is 9 m (29.5 ft) in girth.
Ash dieback is caused by the fungus Hymenoscyphus pseudoalbidus which was previously known as Chalara fraxinea. Research into the genetics of the resistance of ash (Fraxinus excelsior) has shown that resistance does occur in European populations, but, at least for the samples tested, it is neither common nor strong.
#SaveTheAsh – YouTube playlist – Ash tree – Fraxinus
The English Horticulturist Edward Step had this to say about the Ash a century ago.
The Ash (Fraxinus excelsior).
So commanding, yet at the same time so light and graceful, does a well-grown Ash appear, that Gilpin called it the “Venus of the Woods.” This may appear to some to be rather too close an approach to the “Lady of the Woods” (Birch), but in our opinion it well expresses the characteristics of the two. They are both exceedingly graceful, but the beauty of the Birch is that of the nymph, whilst that of the Ash is the combined grace and strength of the goddess. I have said “a well-grown” Ash, a phrase by which the timberman would understand a tree that had been hemmed in so closely by other trees that it has had no chance of developing as a tree, but only as a straight stout stick of wood, from eighty to one hundred feet long. My well-grown Ash is in a meadow, where both soil and atmosphere are moist and cool; where it has had elbow-room to reach its long graceful arms upwards and outwards, and to cover them with the plumy circlets of long leaves. It is there, or on the outskirts of the wood, or in the hedgerow, that the Ash is able to do credit to Gilpin’s name for it.
Before the reign of iron and steel was quite so universal, Ash timber was in demand for many uses where the metals have now supplanted it. It was then far more widely grown as a hedgerow tree than is now the case. Selby laments the neglect of this former custom, which kept up a supply of tough and elastic timber, useful in all agricultural operations, and added much to the beauty of the country. No doubt the noxious drip and shade of the Ash have had much to do with this abandonment of it, for few things can live beneath it—a condition helped by its numerous fibrous roots, which quickly exhaust and drain the soil, and so starve out other plants. Although it thus drains the surface soil, it is not dependent upon these upper layers for food, for its much-branched roots extend very deeply in the porous soils it prefers. It must not be supposed from the foregoing remarks that the Ash is confined to the lowlands. In Yorkshire it is found growing at an elevation of 1350 feet; in Mid-Germany it grows as far up as 3500 feet, and in the Alpine districts 500 feet higher still. It has a preference for the northern and eastern sides of hills, where the atmosphere is moist and cool, and the soil deep and porous, for it loves free and not stagnant moisture for its roots. The bark of both trunk and branches is pale grey, and some look to this as the origin of the tree’s English name. On examining the leafless branches in early spring, two things strike the observer—the blackness of the big opposite leaf-buds, and the stoutness of the twigs. This latter fact is due to the great size of the leaves they have to support, which implies a considerable strain in wind or rain. What are generally regarded as the leaves of the Ash are only leaflets, though they are equal in size to the leaves of most of our trees. The largest of the leaflets are about three inches in length, and there are from four to seven—mostly six—pairs, and an odd terminal one, to each leaf. They are lance-shaped, with toothed edges. The leaves are late in appearing, but, like Charles Lamb and his office-hours, they make up for it by an early departure.
Flowers of Ash.
The flowers of the Ash are very poor affairs, for they have neither calyx nor corolla, though their association in large clusters makes them fairly conspicuous as they droop from the sides of the branches in April or May. Stamens and pistils are borne by the same or separate flowers, and both kinds or one only may be found on the same tree. The pistil is a greenish yellow pear-shaped body, and the stamens are very dark purple. The flowers are succeeded by bunches of “keys”—each one, when ripe, a narrow-oblong scale, with a notch at one end and a seed lying within at the other. The correct name for these is samaras. In looking at a bunch of these “keys”—they are something like the keys to the primitive locks of the ancients—one is struck by the fact that they all have a little twist in the wing or sail, which causes the “key” to spin steadily on the wind and reach the earth seed-end first. They are, therefore, sometimes known as “spinners.” These are ripe in October; but though the trees produce seed nearly every year after the fortieth, one may chance to look at a dozen Ashes before he comes upon one that bears a seed. The reason for this lies in the fact that some trees have no female blossoms. The seeds do not germinate until the second spring after they are sown.
Bole of Ash.
Much of the Ash-wood in use for carriage-poles, oars, axe and hammer shafts, and similar purposes where only small diameters are needed, are obtained from Ash-coppice, which rapidly produces well-developed poles. So strong and elastic is the Ash timber when taken from young trees, that it is claimed it will bear a greater strain than any other European timber of equal thickness. The Ash is not one of the long-lived trees, its natural span being about two hundred years, but its wood is regarded as best between the ages of thirty and sixty years.
Cattle and horses are fond of Ash leaves, which were formerly much used for fodder, and still are in some districts; but it is said that to indulge cows in this food is fatal to the production of good butter from their milk. In some country places there is still extant a “Shrew-Ash”—a tree into which a hole has been bored sufficiently large to admit a living shrew-mouse, which has then been plugged in, to die of suffocation. A touch of a leaf from this tree was reputed to cure cramp, but especially that form of it supposed to be caused by a shrew passing over man or beast. Then there was the Ash whose bole had been cleft that it might be a “sovran” remedy for infantile hernia. It is difficult to account for the origin of these ideas, but they are deep-rooted and die hard. John Evelyn remarks of this latter superstition: “I have heard it affirmed, with great confidence and upon experience, that the rupture, to which many children are obnoxious, is healed by passing the infant through a wide cleft in the bole or stem of a growing Ash-tree; it is then carried a second time round the Ash, and caused to repass the same aperture as before. The rupture of the child being bound up, it is supposed to heal as the cleft of the tree closes and coalesces.” The origin of the name Ash is uncertain, though many fanciful suggestions have been made in explanation of its meaning. Its Anglo-Saxon form was æsc, a word used by the same people for spear, but that was because their spear-shafts were made of Ash-wood.
Agrilus planipennis, commonly known as the emerald ash borer.
Agrilus planipennis, commonly known as the emerald ash borer, is a green jewel beetle native to eastern Asia that feeds on ash species. In its native range, it is typically found at low densities and is not considered a significant pest.
Outside its native range Agrilus planipennis, the emerald ash borer, is destroying native ash (fraxinus) species.
It is only a matter of time until it reaches the UK.