Houseplants: What Are the Methods of Plant Seed Dispersal?

As urbanization levels rise higher and higher, many children grow up in cities and are unfamiliar with some of the basic laws of nature, especially the ways in which the various plants they see everywhere in daily life reproduce and grow - basically no one knows about them. So what are the main routes and methods of plant seed dispersal? One is with the help of external forces, such as wind, water, and being carried by animals and humans; the other is relying on the plant's own generated force. Below I will introduce you to the different plants that use each of these dispersal methods.

1. Dispersal by wind

Seeds that spread with the help of wind are usually lightweight, able to float in the air, and move everywhere with the wind. Some plant seeds even grow special structures suited to flying with the wind. For example, the fine hairs on cotton and willow seeds; the umbrella-like pappus on dandelion fruits; the part of the fruit coat and seed coat of plants such as pine, maple and elm that spreads out into wings; and the membranous air sacs on the fruits of Physalis. In spring, willow catkins fly everywhere. Grab a clump of willow catkins and look carefully, and you will find some small particles inside - those are the seeds of the willow tree. The willow tree relies on the drifting of its catkins to spread its seeds in all directions.

2. Dispersal by humans and animals

Some seeds have bristles, barbs or the ability to secrete sticky fluid on their outside. With just a light touch, they immediately stick to people's clothes or the fur and feathers of animals. By the time you notice them and pick them off, tossing them casually to the ground, their wish to disperse has already come true - for example, cocklebur, Torilis, and beggarticks.

Fleshy-fruited plants such as cherries, wild grapes and wild ginseng rely on small birds or other animals eating the seeds into their stomachs; since the seeds cannot be digested, they are excreted with the droppings and spread in all directions. And when humans eat these delicious fruits, they often throw the pits away casually, unintentionally becoming "messengers" of seed dispersal.

There are also nut-type seeds, such as chestnuts and pine nuts, which are the favorite food of squirrels. They are carried home by squirrels and stored away; some are eaten, and the rest take root and sprout the following year.

3. Dispersal by water

Plants that grow in water and marshes often rely on water to carry their seeds. For example, the fruit of the lotus that we commonly see - that is, the lotus seed pod - is shaped like an inverted cone and is light, so it can float on the water surface like a little boat, drifting everywhere with the current and at the same time spreading the seeds far and wide.

There is also the coconut among land plants; its fruit has even more multiple functions. The mesocarp of the coconut is very loose and rich in fiber, allowing it to float in water, while the endocarp is extremely hard and thick, protecting the seed from erosion by seawater. The fruit also contains a large amount of coconut water, enough to supply the nutrition and moisture needed when the seed germinates, which enables the coconut to germinate under salty water conditions. The many coconut groves distributed along tropical coasts are inseparable from this ability of the coconut.

4. Dispersal by the plant's own force

In the bean pods we commonly see, when they mature, the dry and hard fruit coat, baked under the scorching sun, often bursts open with a "pop", and the seeds are shot into the distance like bullets fired from a gun barrel. Therefore, for economic crops such as soybeans, rapeseed and sesame, once they mature they must be harvested in time; otherwise the seeds will scatter across the field and cause people losses. The mother garden balsam uses a method similar to the mother pea plant: after the garden balsam fruit matures it bursts open, and the mother garden balsam uses this method to send the seeds in all directions.

Some plants also have special devices for sowing seeds automatically. There is a plant called "squirting cucumber", which produces small, unattractive melons covered with prickles. Do you know its secret? When the fruit matures, at the slightest touch it will fall off and in an instant squirt the seeds from inside out through the top, with a range of up to 6 m; that is how the "squirting cucumber" got its name. The most interesting is the seed of wild oats growing in wheat fields - it can "crawl" into the soil by itself. The outer shell of the wild oat seed has a long awn, which rotates or straightens as air humidity changes. As the awn keeps bending and stretching, the seed moves forward little by little, and once it encounters a crack it will drill in, then take root and sprout the following year. Of course, wild oat seeds "crawl" quite slowly, advancing only 1 cm in a whole day and night, yet this seed-dispersal ability has reached the pinnacle of perfection.

Through the above detailed introduction to the growth habits of various plants and the routes and methods of seed dispersal, it is mainly divided into two major categories: whether external forces are used or the plant's own force is relied upon, and each major category is further divided into several subcategories. Through this summary of dispersal methods and the introduction of actual plant dispersal, have you gained a deeper understanding of the laws of nature? Whether it is plants in nature, or humans, animals and so on, reproducing their own offspring has always been an extremely important part of the process of growth and evolution.