Distribution of fruits and seeds (according to V. N. Korsunskaya)

Distribution of fruits and seeds (according to V. N. Korsunskaya)

In late April - early May, walking along the banks of the river, overgrown with willows, it is easy to get into a real "blizzard". White flakes, like snow, fly from trees and bushes. Under the trees, between the bushes, you can rake them with your foot into piles. Small reservoirs are covered with a thick fluffy carpet so that the surface of the water is not visible. But is it snow?

Let's take a fluff sticking to the sleeve of the dress, examine it through a magnifying glass. It is clearly seen that this is a seed surrounded by a bunch of long white hairs. The bundle plays the role of a parachute, with the help of which the seed is carried by the wind over long distances. The fruit of the willow is a box. When the willow bolls mature, they burst and the seeds are sown from them. Parachutes of seeds spread, seeds fly. Such a device increases the area of ​​\u200b\u200bresistance to air when falling. Therefore, the seeds can soar in the air for a long time and fly far from the mother plant. Poplar and aspen also have parachutes - tufts of hairs around the seeds. It also snows in the poplar alley when the fruits open with the first heat and seeds are sown from them.

Seeds and fruits of many weeds are equipped with tufts, tufts of hairs. Their flying devices are very diverse in their design.

In many plants, flying achenes are placed in baskets, heads, boxes. In wet weather they are closed. The hair bundles are compressed. As soon as the weather becomes drier, the baskets or heads with achenes open.

Hairs, tufts - parachutes of achenes - quickly straighten out, spread out. Due to this, the seeds are at the edges of the baskets. The wind picks them up and the journey begins.

The flying devices of plants are far from being exhausted by hairs and fluff. It is worth going to the forest in the midst of leaf fall to observe the various ways of adapting to the flight of fruits and seeds in their action.

Usually in late autumn you can see how the seeds and fruits of most of the trees that form the upper canopy of a broad-leaved forest are scattered around in the wind. Sometimes the crowns of trees are already completely exposed, and the fruits of linden, ash, American maple still hang on bare boughs. The exceptions are elm and aspen. Already at the very beginning of summer, under the elms, the soil is completely dotted with flat greenish achenes-lionfish of these plants.

Most of the trees in the upper canopy of the broadleaf forest spread their fruits with the help of the wind. The fruits of these trees are small. For example, 50,000 aspen fruits weigh only 4 g. And there are plants whose fruits are many times lighter.

Winged birch fruits can fly away from the mother plant for 1.6 km. Much further away from the spruce can be its seeds, which spill out of the cones in winter. Their wings are like a sail. And the seeds slide on the crust. Like a boat under sail, they rush with a fair wind far, far from their native forest. And maple lionfish travel within relatively short distances - only 0.09 km. Not far from the native tree, ash lionfish fly off - only 0.02 km.

In some plants, parachutes consist of branched hairs resembling a bird's feather - this further increases the sail surface of the parachute. In this regard, the fruits of the purple sow thistle weed plant may perhaps be in the first place. One sow thistle plant produces up to 35,000 fruits. Each fruit has a dense white tuft of feathery hairs. Such fruits can fly away in the wind for a great distance.

Many of us had to notice that under the fence, near the walls of the hedges, thistles and thistles often grow. The fence stopped the progress of the fruits of these plants. Many weeds grow along the boundaries, ditches and ravines, where the fruits also linger.

Of course, a great many fruits and seeds perish in nature, but some of them can settle on the eaves of a balcony, the roof of a stone house, and an even smaller part will give young seedlings. It may happen that a poplar will grow on the roof, or even groups of trees or thickets of fireweed will grow there.

In a number of plants, flying devices help not only to move seeds, but also to bury them in the ground, like a gimlet.

In the steppes, the wind picks up whole plants, breaking them at the root, and carries them, rolling them from place to place. Tumbleweed - that's what the people called wind-driven, jumping dry plants. Rolling across the steppe, jumping up, hitting the ground, bumping into ditches, hillocks and other obstacles, the tumbleweed scatters seeds over long distances.

Ants play a significant role in the distribution of fruits and seeds. Anyone who has been in the forest knows well these forest inhabitants and their amazing structures; I saw, of course, more than once how ants drag seeds of various plants to their anthill, for example, celandine, Corydalis, Chistyak, fragrant violet.

Probably, many had to meet abundant thickets of celandine near anthills. This plant has light green, delicate, deeply pinnate leaves. To the top of the stem, the leaves are smaller than the lower ones. The stem is covered with sparse protruding hairs and has golden-colored juice, which is used in folk medicine to remove warts. For this, celandine is also called a warthog or jaundice. But the ants in this medicinal plant are attracted not by the tenderness of the foliage, not by the golden flowers, not by the fruits in the form of long pods, but by the seeds with an appendage.

In celandine, the seeds are black, with a large fleshy white appendage. Ants willingly eat these appendages. Because of them, the ants drag celandine seeds, which are quite heavy for them, to their anthill. Very often, ant roads are littered with celandine seeds with bitten off appendages. Ants will drag celandine seeds into the anthill, but they themselves do not eat them. The appendages are separated from the seed by a dense skin. Under it, the seeds remain intact. The next year, the seeds germinate in the anthill, through its walls, and on the way to it.

In summer, it is interesting to watch the ants taking away seeds and fruits. Ants, with the help of their sensitive organs of smell and touch, located on the antennae, look for seeds. In addition to the plants already mentioned, it can be hoof, Ivan da Marya, coppice, goose onion. But almost always these are seeds of early-flowering plants, the fruits of which ripen no later than mid-summer. Closer to autumn, ants stop collecting seeds.

In nature, almost all animals can be direct or indirect distributors of seeds over long distances from the mother plant.

KNOWN

That the appearance of cherries in Europe is associated with the famous Roman commander Luculus. This happened in 64 BC. e. After the victories of Luculus in Asia, there was a solemn entry into Rome. The commander's chariot was decorated with cherry branches, which had long been cultivated as a cultivated plant in Iran and Asia Minor.

In the age of technological progress, the seeds of many plants can "roam" on car tires and aircraft chassis, cross rivers and seas on barges and motor ships, and then germinate in a new place.