Fraxinus excelsior

In winter the ash is very easily known by its hard black buds which are arranged in opposite pairs. The twigs are flattened at each joint where the buds are set and this flattening takes place alternately in two planes. The bark of ash is a characteristic pale grey: smooth at first it becomes regularly ridged and furrowed as each stem grows stouter and older.

Ash leaves (Figure 40) are large and pinnateiy compound. This means that they consist of several separate leaflets, set in pairs along opposite sides of a central stalk, which ends in a solitary terminal leaflet The number of leaflets varies, but is commonly 7, 9,11, or 13; their edges bear shallow teeth. The seedling has a very different appearance, for it starts life by bearing two oval, seed-leaves, which are followed by two larger, pointed-oval true leaves; the leaves of the next pair have only three leaflets each, but succeeding ones grow steadily larger, with more numerous leaflets.

The flowers of ash open in ApriL before the leaves expand. They are catkin-like in structure, although the ash is not closely related to other common catkin-bearing trees. As our drawing shows, the flower clusters may be dense with short stalks to each

Tree Bearing Catkins

flower, or more lax and open. Each individual flower is very small, and has no apparent sepals or petals. Many flowers are all-male, and consist of nothing more than a pair of stamens. Others are hermaphrodite, with both male stamens and a female pistil, while others again are all-female, and lack stamens. Each tree may bear flowers of one type, or of two or three kinds together.

After fertilisation by the wind, the pistils ripen rapidly through the summer, and soon each female or hermaphrodite flower-duster has expanded into the familiar bunch of ash 'keys.' Ash fruits are so-called because each seed, with its attached wing, has the outline of an old-fashioned key used for opening doors or chests. At first the seeds are green, and if gathered at that stage and sown at once, they will sprout without delay. If they are left to ripen they change to brown in colour, and become doimant. This means that if they are sown later they will not germinate until IS months after they first ripened. In practice the forester mixes his ripe ash seed with damp sand and stores it in a well-drained pit out of reach of birds, mice and squirrels, until the time for spring sowing comes round, 18 months after storage began.

hgure 58

Winter twigs and buds of ash (life size).

Left a single terminal bud. showing the hard black scales (x 3).

Fruit Fraxinus Excelsior Drawing

hgure 58

Winter twigs and buds of ash (life size).

Left a single terminal bud. showing the hard black scales (x 3).

Ash forms a tall upstanding tree with a wide-spreading crown because the side-buds are set in opposite pairs, the branches are very apt to fork; in fact they do so whenever anything happens to the terminal bud Ash comes into leaf late, seldom before May, and it loses its leaves earlier in October than do most other trees. These points make it a poor shelterbelt tree, though it is very hardy and can thrive far up the hills. It likes a rich soil and grows best on deep loams over limestones.

The timber of ash is easily distinguished by its well-marked annual rings. Each ring has a thin band of open springwood pores, and outside this comes another band - thick or thin - of hard dense summerwood tissue. When ash grows fast it forms a broad summerwood band, and is then exceptionally strong.

Ash is the toughest of our native timbers, so it is chosen wherever there is need to absorb a hard blow or shock without splintering. It is used for the stronger handles, including those for hammers, axes, spades and pick axes. Sportsmen use it for hockey sticks and oars, and the rims of wooden cart wheels are always made up of ash felloes. Ash is widely used in furniture, because of its strength and attractive grain, and also because it can easily be bent to curved outlines.

FIGURE 39 (lift)

Fraxinus Excelsior

figure 40

A cluster of ash fruits, or keys*, ripening in October. Each fruit consists of a single winged seed. A compound leaf is seen behind (all X?).

figure 40

A cluster of ash fruits, or keys*, ripening in October. Each fruit consists of a single winged seed. A compound leaf is seen behind (all X?).

figure 41

Flowering twigs of ash in April (x|). Left: a dense group of male inflorescences.

Right: a tax inflorescence that includes both male and hermaphrodite flowers.

Centre left: a male flower with well-developed stamens.

Centre right: a hermaphrodite flower with two small stamens and a central pistil (X8).

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