The fertilized egg cell develops into an embryo which, with certain reserve tissues, forms the seed which is enclosed in a protective covering called the seed coat.
Simultaneously, however, there are great losses both of the seeds and the young plants. Large quantities of seeds are eaten by birds and animals and many fall in places unsuitable for growth where they either do not germinate at all or die shortly after germinating, having used up the store of food in the seed. Similarly, many young trees are destroyed in their first years by drought, frost, invading grass or other plants, or by animals that feed on them. Of the huge crop of seeds, all that usually remains within a few years is less than one per cent per hectare.
In most conifers the seeds are contained in a cone consisting of carpels attached to a central axis that becomes woody.
The fruits of broad-leaved trees are classified as true fruits if their origin is a single ovary, or accessory fruits if other parts of the flower are involved, or if their origin is the entire inflorescence (mulberry).
Birch and pine, the first pioneers, were followed by the rapid northward spread of the oak and hazel, whose heavy seeds fall only a few metres from the parent Fee. Acorns, however, are a favourite food of jays and pigeons, while hazelnuts are eaten by nutcrackers and woodpeckers and e sometimes carried great distances in their beaks.
Naturally, it would drop to the ground while being carried; and thus the offipring of a given tree might take root several hundred kilometres from the parent. In this way even these trees migrated hundreds of kilometres to the north within Itirly short space of time.
Simultaneously, however, there are great losses both of the seeds and the young plants. Large quantities of seeds are eaten by birds and animals and many fall in places unsuitable for growth where they either do not germinate at all or die shortly after germinating, having used up the store of food in the seed. Similarly, many young trees are destroyed in their first years by drought, frost, invading grass or other plants, or by animals that feed on them. Of the huge crop of seeds, all that usually remains within a few years is less than one per cent per hectare.
In most conifers the seeds are contained in a cone consisting of carpels attached to a central axis that becomes woody.
The fruits of broad-leaved trees are classified as true fruits if their origin is a single ovary, or accessory fruits if other parts of the flower are involved, or if their origin is the entire inflorescence (mulberry).
Birch and pine, the first pioneers, were followed by the rapid northward spread of the oak and hazel, whose heavy seeds fall only a few metres from the parent Fee. Acorns, however, are a favourite food of jays and pigeons, while hazelnuts are eaten by nutcrackers and woodpeckers and e sometimes carried great distances in their beaks.
Naturally, it would drop to the ground while being carried; and thus the offipring of a given tree might take root several hundred kilometres from the parent. In this way even these trees migrated hundreds of kilometres to the north within Itirly short space of time.
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Garden planning design should be fairly detailed and specific and include an indication of the type of planting envisaged in the different garden beds.
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