Dispersal of tree seeds by water, as in the case of certain water plants, occurs less frequently. Of the European trees the older is one whose seeds are dispersed by water as well as by the wind, and of the tropical species the coconut palm is a noteworthy example.
The fruit is a ripened ovary, its walls forming the seed vessel, and contains one or more seeds.
To ensure that they fall in a suitable open space and do not merely drop beside the parent tree, where the prospects for their further growth are poor, the seeds are adapted for dissemination to longer or shorter distances. Most are equipped for dispersal by the wind and are either covered with down (willow, poplar) or have membranous wings (birch, elm, pine, spruce) or thick wings (maple, lime, hornbeam). The seeds of another group of woody plants are dispersed by animals, mainly birds. In general these are trees with pulpy, bright coloured fruits which serve as food for the birds, the seeds then being disseminated over a wide area in their excrement (mountain ash, cherry, yew).
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.
Dry fruits with a dry and hard outer wall are Samara - usually a winged, one-seeded fruit with thin, membranous to leathery coat (birch, elm, ash); Nut - a one-seeded fruit with hard, woody wall not connected with the seed (hazel, lime, hornbeam); Legume - usually the product of two carpels splitting along two lines of suture when ripe and containing several seeds; characteristic of most members of the family Leguminosae; Capsule - a single or several valved fruit splitting in various ways when ripe and containing several seeds (poplar, willow, chestnut). Fleshy fruits have soft, fleshy walls; Drupe - usually a one-seeded fruit with a coat comprising three layers: a thin outer layer, middle fleshy layer and a hard bony layer - the stone encasing the seed (cherry, walnut); Berry - a fruit with thin membranous covering and fleshy centre with one or several seeds embedded in the pulpy mass; few trees bear true berries. - 15266
The fruit is a ripened ovary, its walls forming the seed vessel, and contains one or more seeds.
To ensure that they fall in a suitable open space and do not merely drop beside the parent tree, where the prospects for their further growth are poor, the seeds are adapted for dissemination to longer or shorter distances. Most are equipped for dispersal by the wind and are either covered with down (willow, poplar) or have membranous wings (birch, elm, pine, spruce) or thick wings (maple, lime, hornbeam). The seeds of another group of woody plants are dispersed by animals, mainly birds. In general these are trees with pulpy, bright coloured fruits which serve as food for the birds, the seeds then being disseminated over a wide area in their excrement (mountain ash, cherry, yew).
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.
Dry fruits with a dry and hard outer wall are Samara - usually a winged, one-seeded fruit with thin, membranous to leathery coat (birch, elm, ash); Nut - a one-seeded fruit with hard, woody wall not connected with the seed (hazel, lime, hornbeam); Legume - usually the product of two carpels splitting along two lines of suture when ripe and containing several seeds; characteristic of most members of the family Leguminosae; Capsule - a single or several valved fruit splitting in various ways when ripe and containing several seeds (poplar, willow, chestnut). Fleshy fruits have soft, fleshy walls; Drupe - usually a one-seeded fruit with a coat comprising three layers: a thin outer layer, middle fleshy layer and a hard bony layer - the stone encasing the seed (cherry, walnut); Berry - a fruit with thin membranous covering and fleshy centre with one or several seeds embedded in the pulpy mass; few trees bear true berries. - 15266
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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.
