It is interesting

Water hyacinth, or green plague

Both of these names belong to the same plant, which, in fact, is not surprising. After all, some species have names and maybe more. For example, the well-known common tansy (Tanacetum vulgare) in various regions of Russia, as soon as it is not named: worm, nine-leaf, nine-leaf, goat, mountain ash, button-garden, romance, hazel-cherry, susik.

But in our case, it is interesting that the name of the plant in question is strictly associated with geography. In the south, in the tropics and subtropics, it is not called otherwise than "green, or water plague", and in countries with a temperate climate, everyone lovingly calls it water hyacinth. Although not a plague, nickname hyacinth is an aquatic plant - Eichornia tolstonozhkovaya(Eichornia crassipes) from the pontederia family (Pontederiaceae) has nothing to do with it.

Probably, many tropical countries of the world would be richer now, they would not have to spend huge amounts of money on many years of struggle with one of the most dangerous aquatic weeds, if visitors to the cotton exhibition in Texas limited their interests only to its main exhibit. But first things first.

In that distant 1884, as today, the organizers of the exhibition invented various "baits" to attract visitors. Then, in addition to the usual attractions and cheap sales, a special "zest" was prepared. In the center of the room, in a small pond, floated an outlandish plant from Venezuela with emerald leaves and elegant lilac-purple racemose inflorescences that resembled hyacinths.

Visitors to the exhibition were eager to buy tropical “exotic” rosettes for their ponds and pools. These plants multiplied surprisingly quickly. Happy owners gave away luxurious flowering specimens to neighbors.

But very soon the general admiration gave way to anxiety. Along with undeniable decorative merits, the handsome man had one unpleasant property - an amazingly high rate of vegetative reproduction. One outlet in 50 days formed up to 1,000 offspring, each of which, in turn, began to share again. And without higher mathematics, it is easy to calculate that in 3 months one plant turned into a million, and in six months - into a trillion copies!

Such figures for any of our plants are a real curiosity, because out of a huge number of its descendants, only a few survive. Therefore, the Earth is not completely covered with extremely fertile dandelions, dandelions or birches. But in the case of the water hyacinth, the situation was different. Eichornia brought from afar under the new conditions was absolutely not damaged by anything and was not eaten by anyone. And that is why she appeared in the "school of Nature" as a rare visual aid, showing that, in principle, this nature is capable. From a lovely ornamental plant, water hyacinth was rapidly turning into a "green plague" - a malicious weed that inhabits water bodies.

Its violent reproduction and the ability to live, not only attaching itself to the ground, but also floating freely on the water mirror, led to the fact that in the southern United States, eichornia quickly covered the surface of many reservoirs: slowly flowing rivers, ponds, lakes and even huge reservoirs. The exotic plant has become an obstacle to navigation, fishing, irrigation, literally clogging irrigation canals. Getting on rice checks, it covered them with a solid carpet, dooming the peasants to starvation.

It seemed that it was already impossible to stop the spread of Eichornia around the world. For several decades, it has spread throughout all tropical and subtropical regions and filled the reservoirs of Australia, Africa, Asia.

It was necessary to do something about this "green plague". At one time it was assumed that the unlimited growth of the weed could be hindered by animals. In Africa, high hopes were pinned on hippos.However, even these giant plant eaters did not live up to expectations - the rate of reproduction of the eichornia exceeded the rate of its absorption. Mechanical methods of struggle did not give tangible results: mowing, pulling. Only the use of the 2,4-D herbicide sprayed from airplanes or special ships made it possible to purify water bodies for a short time. But the use of this dangerous drug was soon banned everywhere.

Huge amounts of money were spent on the fight against the green scourge. And all in vain - the "green plague" clearly emerged victorious in this battle.

But, as it happened more than once in history, man still found a way out of a seemingly hopeless situation. The biological method helped to cope with the aquatic weed, the essence of which is that in order to combat a foreign organism, natural enemies are brought in, which restrain the rate of its reproduction. Scientists have found them in South America - several species of weevils, herbivorous mites, moth moths. After it was proved that these invertebrates cannot eat anything but eichornia, they were bred in all countries where it raged, and released into water bodies.

Having discovered countless food supplies, gluttonous insects and mites began to multiply and spread rapidly. Literally before our eyes, among the dense thickets of eichornia, "holes" began to appear, the plant was clearly weakening and gradually receded under the onslaught of eaters that appeared.

By that time, eichornia had already been used in many countries. It began to be widely used as fertilizer and for livestock feed. And in India, they even developed a method for producing paper from eichornia green mass.

So the person managed to cope with the environmental problem, which he himself gave rise to. This time, the genie was driven back into the bottle.

Recently, water hyacinth has appeared in the markets of Moscow and a number of other cities in Russia. It can only be assumed that he was delivered here not from the deep rivers of South America, but from the south of Europe or from the irrigation canals of Turkmenistan, where he settled in places. Our eichornia, of course, will not become a "green plague". Even, on the contrary, it will enrich the flora of backyard ponds. It should only be remembered that in winter it will inevitably die in open reservoirs. But the content of "hyacinth" in the cold season in a vessel with water (at a temperature of 15-220C, preferably additional lighting) or in an aquarium is quite possible. And in spring, transferred to the heated water of the garden reservoir, the plant will begin to multiply and delight with emerald greenery and beautiful inflorescences.

S. Izhevsky,

Doctor of Biological Sciences

(Based on the materials of the magazine "Floriculture", No. 3, 2003)