The branch of science concerned with the interrelationships of living organisms and their environment is called ecology. The ecological factors that in great part determine the general disribution of the various tree and shrub species are tempera, uo and moisture.
Particularly great are the differences in the temperature requirements of the various species; that is the principal factor limiting their occurrence and determining the yrs that can be cultivated in a given environment.
The area where shrubs grow naturally in the wild is called the area of natural distribution and may best be depicted on it map. When we compare the areas of distribution of the various species it is evident that some require specific temperature levels since they occur, for instance, only in southern Europe or only in coastal regions or only in a continental limate. On the other hand, some are very adaptable and grow throughout most of Europe from south to the far north, often beyond the Arctic Circle. Examples includes the dog rose, blackthorn, and water elder.
Discernible below the buds is the leaf scar where the leaf was attached to the twig. Leaf scars vary in size and often have a characteristic shape. The leaf scars of the common elder, red elder, staghorn sumach and bladdernut are quite large. Sometimes the part of the twig below the bud is swollen and this spot is called the peg.
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.
Thorny or spiny twigs are characteristic of the barberry, gooseberry, blackberry, blackthorn, hawthorn, sea buckthorn, common buckthorn, box thorn, and all roses. Slightly angular are the twigs of the common elder, red elder and water elder, markedly angular are those of the traveller's joy and common broom.
Particularly great are the differences in the temperature requirements of the various species; that is the principal factor limiting their occurrence and determining the yrs that can be cultivated in a given environment.
The area where shrubs grow naturally in the wild is called the area of natural distribution and may best be depicted on it map. When we compare the areas of distribution of the various species it is evident that some require specific temperature levels since they occur, for instance, only in southern Europe or only in coastal regions or only in a continental limate. On the other hand, some are very adaptable and grow throughout most of Europe from south to the far north, often beyond the Arctic Circle. Examples includes the dog rose, blackthorn, and water elder.
Discernible below the buds is the leaf scar where the leaf was attached to the twig. Leaf scars vary in size and often have a characteristic shape. The leaf scars of the common elder, red elder, staghorn sumach and bladdernut are quite large. Sometimes the part of the twig below the bud is swollen and this spot is called the peg.
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.
Thorny or spiny twigs are characteristic of the barberry, gooseberry, blackberry, blackthorn, hawthorn, sea buckthorn, common buckthorn, box thorn, and all roses. Slightly angular are the twigs of the common elder, red elder and water elder, markedly angular are those of the traveller's joy and common broom.
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In garden planning, variations on color, texture, shape of reconstituted stone blocks will add autenticity to your garden.
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