Buds are young undeveloped shoots containing leaves and sometimes flowers. They are an important means of identification in winter when trees and shrubs are leafless. The terminal bud is located at the tip of a twig or branch and is usually solitary (in most species of shrubs), though there may also he two, e.g. in the lilac and bladdernut. Lateral buds are formed in the axils of the leaves and are alternately arranged, e.g. in the rose, currant, willow, or opposite, i.e. paired on either side of the twig, as in the common elder, cornelian cherry,'rivet, etc. In some species these buds are not always exactly pposite each other and are called subopposite, e.g. the spindle ree, privet and buckthorn. Flower buds vary greatly in shape, especially in the case of early flowering species such as cornelian cherry, Japanese quince, blackthorn and sea buckthorn.
In most woody plants the buds are clearly visible. Only in rare instances are they enclosed by the leaf stalk base and concealed from view until the leaf falls. Such buds are found, for instance, in the mock orange (Philadelphus). Small, hard or leathery leaves known as scales protect buds against damage from heat, cold and drying winds.
On rupturing the seed coat the first root turns downward due to the pull of gravity, thus anchoring the emerging seedling in the soil. The hypocotyl or first stem then grows up towards the soil surface, where it straightens and pulls up the two green cotyledons. These are an important part of the seedling since they contain food reserves for the initial period of growth and also chlorophyll for making new food by means of photosynthesis. The deciduous shrubs of Europe all have two cotyledons that differ in shape from the true leaves.
Other shrubs extend far to the north but do not occur in southern Europe with its warm climate. Such typical northern species are the European black currant and willow spiraea.
In some woody plants a further good means of identification is the twig, the various distinguishing features being its thickness, colour, pubescence, thorniness, angularity and sometimes also the number of corky pores or lenticels.
Hypogeal germination is more common in trees with large seeds; in the case of shrubs that are found only in Corylus avellana, Rhamnus frangula and Daphne mezereum. All other shrubs are characterized by epigeal germination. - 16035
In most woody plants the buds are clearly visible. Only in rare instances are they enclosed by the leaf stalk base and concealed from view until the leaf falls. Such buds are found, for instance, in the mock orange (Philadelphus). Small, hard or leathery leaves known as scales protect buds against damage from heat, cold and drying winds.
On rupturing the seed coat the first root turns downward due to the pull of gravity, thus anchoring the emerging seedling in the soil. The hypocotyl or first stem then grows up towards the soil surface, where it straightens and pulls up the two green cotyledons. These are an important part of the seedling since they contain food reserves for the initial period of growth and also chlorophyll for making new food by means of photosynthesis. The deciduous shrubs of Europe all have two cotyledons that differ in shape from the true leaves.
Other shrubs extend far to the north but do not occur in southern Europe with its warm climate. Such typical northern species are the European black currant and willow spiraea.
In some woody plants a further good means of identification is the twig, the various distinguishing features being its thickness, colour, pubescence, thorniness, angularity and sometimes also the number of corky pores or lenticels.
Hypogeal germination is more common in trees with large seeds; in the case of shrubs that are found only in Corylus avellana, Rhamnus frangula and Daphne mezereum. All other shrubs are characterized by epigeal germination. - 16035
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In garden planning, variations on color, texture, shape of reconstituted stone blocks will add autenticity to your garden.
