Growing Plants
Dispersal of Seeds
In natural way plants scatter their seeds in order to ensure that they do not grow too close to one another for their proper growth.
The process by which the seeds are scattered away from the mother plants is called DISPERSAL or Dispersal of Seeds.
There are many ways of dispersal of seeds.
Dispersal of Seeds by Wind:
Wind helps to carries seeds far away from the parent plants. Seeds of some plants, like Dandelion, Sycamore and Cotton are very light. Such plants have wing and hair on their seeds. These wings help seeds to float with wind. Wind disperse to other place far from parent plants.
Example:
Cotton seeds have fluff around them. These fluffs help the seeds of cotton plants to float away with wind.
Dispersal by animals
Human, animals and birds are help to dispersal of seeds. Animals and humans being eat some fruits and throw away the seeds, which grow into new plants. Seeds of many plants pass through the digestive system of animals and birds. Seeds remain undigested in animals stomach and are dispersed to other areas by droppings.
Example:
Crow and other birds eat fruits of Peepal, Banyan tree, etc. Seeds of these trees remains undigested and are dispersed by droppings to far places.
Seeds of certain plants have hooks, stiff hair, or spines, which help in their dispersal.
Example:
Cockleburr seeds have spines which get stuck with the fur of animals and are dispersed at other places.
Dispersal by water
Many plants such as coconut, lotus, etc. disperse their seeds by water. Seeds of such plants are spongy or having fibrous covering, which helps them to float on water.
Example:
Coconut plants usually grow nearby sea or ocean. Coconut seeds fall into water and travel to far places. Coconut can travel several thousand kilometers across oceans. The coconut palms on islands of South Sea grew from coconuts carried there by ocean current.
Dispersal by explosion
Fruits of some plants like pea, bean and poppy burst open when they are ripen, scattering the seeds in all directions. This mechanism of seed dispersal is called explosion.