Trees and shrubs are perennial plants whose stems become woody and last for many years. Trees usually have a single erect stem or trunk which at a certain height branches out to form a crown, whereas shrubs branch from near to, or at, ground level.
Trees and shrubs are also differentiated according to height. Small trees attain, a height of about eight metres, those of the second category fifteen to twenty-four metres, and those of the first category more than twenty-five metres. The thickness of a tree is usually given by the diameter of the trunk measured at breast height, i.e. 1.3 metres above ground.
In other words, tree with buds arranged in spirals has the leaves also arranged in spirals. Buds are protected against drying out and frost damage by modified leaves known as scales; either by just single scale (willow or plane tree), two scales (alder), or several scales (beech, hornbeam and oak). Distinguishing features of the scales are colour and pubescence. Some trees that bloom in early spring can be identified by the flower buds, which are of different shapes, e.g. willow, elm, poplar and cherry.
A further good means of identification in some trees are the short, peg-like projections known as spurs (cherry, apple) on which the flower buds are borne. Some trees' twigs have distinctive large or small leaf scars which remain after the leaves falhe horseshoe-shaped ones of horse chestnut are noteworthy.
Spines and thorns are another good means of identification, e.g. on the twigs of the wild pear, black locust and honey locust. The twigs of other trees have conspicuous lenticels (bird-cherry, white ash), waxy warts (birches) or corky plates (hedge maple and smooth-leaved elm).
Under normal conditions trees are the strongest and fittest members of the plant realm.
Trees and shrubs are also differentiated according to height. Small trees attain, a height of about eight metres, those of the second category fifteen to twenty-four metres, and those of the first category more than twenty-five metres. The thickness of a tree is usually given by the diameter of the trunk measured at breast height, i.e. 1.3 metres above ground.
In other words, tree with buds arranged in spirals has the leaves also arranged in spirals. Buds are protected against drying out and frost damage by modified leaves known as scales; either by just single scale (willow or plane tree), two scales (alder), or several scales (beech, hornbeam and oak). Distinguishing features of the scales are colour and pubescence. Some trees that bloom in early spring can be identified by the flower buds, which are of different shapes, e.g. willow, elm, poplar and cherry.
A further good means of identification in some trees are the short, peg-like projections known as spurs (cherry, apple) on which the flower buds are borne. Some trees' twigs have distinctive large or small leaf scars which remain after the leaves falhe horseshoe-shaped ones of horse chestnut are noteworthy.
Spines and thorns are another good means of identification, e.g. on the twigs of the wild pear, black locust and honey locust. The twigs of other trees have conspicuous lenticels (bird-cherry, white ash), waxy warts (birches) or corky plates (hedge maple and smooth-leaved elm).
Under normal conditions trees are the strongest and fittest members of the plant realm.
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Garden planning of a garden for children should be designed to convert easily to a decorative layout.
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