Quercus rubra

All the true oaks belong to the genus Quercus which is found in temperate zone forests al] round the Northern Hemisphere - in Europe. Asia and America. Oaks have certain marked features that make recognition easy. Winter buds are alternately arranged, but towards the tip of the twigs they form distinct clusters: as a result of this, oaks branch in an irregular pattern.

The flowers are catkins, which open in May. Male catkins are long-stalked, and carry a succession of small flowers. Each separate male flower has a number of bracts and four to five stamens. After shedding pollen, the male catkins fall away. Female catkins, which are carried on the same tree, are shorter, with fewer flowers. Each individual female flower has several bracts and a three- or four-styled pistil. After pollination, the female flower develops the very distinctive fruit - the acorn. Usually this takes only one season, and the acorns are ripe by October, but some kinds of oak take 2 years to ripen their seeds.

Each acorn is a nut or hard, one-seeded fruit. It sits on a litde cup. or cupule, formed by the fusing together of several small leafy bracts to make a hard woody structure. Acorns are spread by animals and birds that eat most of them but scatter or drop others undamaged. When they sprout in the spring, the seed-leaves remain within the acorn: the first shoot bears a few scale leases and then normal foliage. Our word 'acorn' is compounded of two Anglo-Saxon words - ac for oak and corn for seed. The seed crop is called 'mast' a word related to 'meat in the sense of food because they make good food for swine. Heavy crops, or 'mast years,* are irregular. This aids the spread of the oaks, for in a good mast year more seed falls than the birds and beasts, wild or tame, can readily eat. Other features of the oaks vary widely from one kind to another. These include leaf shape, colour and texture, the character of the bark and the quality of the wood.

Quercus Rubra Flower

FIG DUE S3

Above; Flowering twig of Red oak, with leaves unfolding in April, backed by the outline of a mature, flame-shaped leaf. A female catkin is seen on the left male catkins in the centre (xf).

Lower left Single female flower (X7) showing bracts and three stigmas (sometimes four are found). Lower centre: Acorn on its cup (Xi).

Lower right: Single male flower (X 5) with bracts and four stamens (sometimes five are found).

Red oak is one of a number that show good red autumn colours and grow wild in North America. The leaves unfold pale yellow in spring, and are a rich green during the summer. When autumn comes and the leaves fade they blaze out in shades of russet scarlet or crimson. The leaf shape resembles a flame, being a long irregularly-lobed oval, but it is variable. The acorns are round or dome-shaped and take 2 years to ripen. The bark is smooth and grey. The slender winter twigs are illustrated in Figure 84.

The wood of red oak is rather featureless. It is dull brcrwn in

Quercus Rubra Winter Bud

figure 84

Winter twigs and buds of three oaks. (Twigs half natural size; buds magnified 2j times.)

figure 84

Winter twigs and buds of three oaks. (Twigs half natural size; buds magnified 2j times.)

Buds Ulmus Hollandica

colour, reasonably hard and strong, and works well in any direction, but it lacks the remarkable strength, durability and attractive figure of the native English oaks. In America it is used for furniture and small wooden objects, or as firewood. Red oak grows fast even on soils of moderate fertility, but as there is little demand for its wood it is planted solely for ornament You may find it in parks or large gardens, or on the* fringes of certain national forests where it has been planted to add to the varied greens of the timber trees and provide red autumn colours.

Left: Red oak, with slender twigs and narrow, tapering buds. Centre: Turkey oak, with clusters of stipules on every bud. Right: Pedunculate oak. with rugged twigs and stoutly oval buds.

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