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Fruits and seeds of grasses are usually very small and light. They are easily blown away by the wind.
Animals do a lot to carry and spread seeds around. These fruits and seeds have special structures such as hooks, barbs, spines and pointed tips which help them to hitchhike.
A very good example is the Love Grass (Chrysopogon aciculatus). Its spikelets have pointed tips which can easily stick to people's socks and pants as they walk in the fields. They may travel a long way before they are picked off and thrown onto the ground. This is how the fruits are dispersed.
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Some fleshy fruits are eaten by birds and other animals which help to distribute them. Even when they swallow both the pulp and seeds, they may still be distributed. This happens when the seeds pass through the animal's digestive tract and fall to the ground in the animal's droppings.
In all plants that have been mentioned so far, their fruits and seeds need some help either from the wind or animals, to get from one place to another. But some plants have special ways of scattering seeds by themselves, without outside help. The Yellow Wood Sorrel (Oxalis corniculata) is one good example.
After the yellow flowers have been fertilised, the fruits develop into narrow, ridged capsules. Inside each fruit, the seeds are lined up in much the same way that peas are arranged in a pod. As the inner walls of the fruits ripen, they begin to dry up. At a certain point, they bend backward suddenly, forcing the seeds to fly out. These seeds do not usually travel a great distance, but they do scatter widely enough in the area nearby to find room to sprout. Since they have a rough outer coat, they may stick to an animals's fur or feet and be carried further. Many other plants such as the Black-eyed Susan (Thunbergia alata), Common Asystasia (Asystasia intrusa) and Asystasia coromandeliana have fruits which split suddenly and scatter their seeds.
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