Caution - Ambrosia! How to destroy a health hazardous weed?
“It's a sad time!” Eye charm! ”... Coughing and sneezing are heard from all sides! There is only one reason - ragweed, known from literature as the insidious food of the gods, is blooming. Residents of many countries often call it the dust of the devil. What is this plant that has become the scourge of the population, how did it get to us, and is it possible to successfully deal with it? Let's find the answers to the questions together and work out a joint action plan, because ambrosia alone cannot be defeated! This is the first thing to remember about this dangerous weed.
- Why is ragweed very dangerous for humans?
- Environmental Ambrosia
- Where did ragweed come to us from?
- Are all types of ragweed to be destroyed?
- Ambrosia Control Methods
Why is ragweed very dangerous for humans?
More than 80% of the population is susceptible to allergic diseases, and the leading place among the causative agents of allergic reactions is ragweed.
Allergies in adults and children can occur immediately, but sometimes a period of gradual “accumulation” passes (up to 2 years), and a severe acute form of allergy occurs immediately, leading to asthma. It happened to me: 2 years of struggle with wormwood in the country - without visible health consequences, and in the 3rd - the most severe form of asthma. In the 3rd year, a neighbor and a girlfriend in the country also fell ill.
What is the special danger of ragweed? 3-4 microscopic granules of ragweed pollen will cause a rapidly passing cough, but a gap will appear in the immune system that other pathogenic pathogens will “take advantage of”. Already 25 grains of active pollen in 1 cubic meter of air causes an allergy attack (persistent cough, lacrimation, runny nose, etc.). Given that one plant forms several million active pollen particles, the damage to public health can be compared with a global catastrophe.
An absolutely healthy person can become allergic within a few days if the air is filled with pollen from flowering ragweed plants. And this type of allergy is practically incurable.
Information for consideration! From 2000 to mid-August, in Moscow and the region, a peak of ragweed pollen in the air was observed in the amount of 8-15 active pollen particles. In a person with reduced immunity, the manifestation of allergy begins with a concentration of 4 pollen grains per 1 cube. m. area.
The harmfulness of ragweed is not limited to causing great troubles to humans. Its fitness is so high that it can turn the soil into barren soil unsuitable for growing other crops.
According to experimental laboratory studies, ragweed to create 1 kg of its own dry matter takes about 1 ton of water, 1.5 kg of phosphorus and up to 16 kg of nitrogen from the soil and other plants. The rapidly growing vegetative mass does not let in the sun. A dense shade, a "hungry ration" of nutrients sharply reduce the yield and quality of meadow herbs, mixtures, "kill" vegetable crops, especially irrigated ones. 1-2 miniature sprouts during the warm season can grow to 3–4 meters of lawn.
When lactating animals eat blooming ragweed, milk and products from it acquire a sharp unpleasant odor, a bitter repulsive taste.
From the above brief information looms “portrait” of the enemy, which is subject to complete extermination. Find out where the ragweed came to our continent.
Where did ragweed come to us from?
Ambrosia belongs to the group of alien plant species. The true homeland of this representative of weed plants is North America. Having arrived with the import of American agricultural products to Europe in 1873 with red clover seeds, the weed began a victorious, catastrophically fast spread across the countries of the Euro-Asian continent.
Ambrosia pollen is several times smaller than a poppy seed. With a fair wind, it overcomes the distance from the southern regions to Moscow in a few days. In calm, calm weather, its distribution takes 4-6 km from the place of growth. Due to the spreading rate for more than 100 years, the area of its capture on the Euro-Asian continent amounted to more than 5 million hectares.
In 1914, ragweed was first discovered in Ukraine. Having more than 600 natural enemies in the homeland among plants and insects, in new spaces ragweed hardly encounters any opposition to its promotion and capture of new areas. In Russia, ragweed first appeared in the southern regions (Krasnodar Territory), the climate of which corresponds to the weed's environmental requirements in his homeland and is steadily moving to the north and east, including the regions of the Far East.
In Russia, ragweed naturalized in vivo in all the southern regions, in the Black Sea region, the Volga region, in the Caucasus, the southern regions of the Far East, Moscow Region and is actively moving to the north and east, quickly adapting to the climate of these regions.
Are all types of ragweed to be destroyed?
Ambrosia in astrov family (Asteraceae) is highlighted in a separate genus Ambrosia (Ambrosia).
The genus includes about 50 species of one- or perennial plants, but on the Euro-Asian continent, including Russia, there are mainly 3 species that are pollen most dangerous to human health:
- Leaf Ambrosia (Ambrosia artemisiifolia L., 1753);
- Ambrosia is tripartite (Ambrosia trifida L.);
- Holosome ragweed (Ambrosia psilostachya DC).
All of them cause allergies, are quarantine weeds and are subject to destruction. But the first two types of ragweed are annual weeds and, in general, it is easier to deal with them, and the third species is perennial, whose roots winter in the soil and when chopped, each root lobule forms a new plant.
The ragweed turned out to be the most adaptable to the new conditions of life, and it is it that is the main invader of new spaces. The ambrosia severity threshold is 1-2 plants per square meter. m square.
Botanical description of ragweed ragweed
Leaf Ambrosia - annual, environmentally resistant weed. It retains the ability to regrow after 4-5 mowing. The growing season begins with warming the air to + 6 ... + 10 ° C and lasts until the first frost. Forms an aerial mass from 0.2-0.3 to 2.5 m high.
The root ragweed, goes deep to 1-4 m. In 2 months, the root deepens to 1 m. A “powerful pump” pumps out moisture along the entire soil profile, providing a nutrient solution above-ground, quickly growing after mowing, mass. The ragweed stalk is straight, dark green with small grooves, pubescent. Branches well.
Note! Untimely mowing of the aerial mass contributes to increased branching of the stems during regrowth.
The leaves of ragweed are dark green of two types. Upper - with an almost solid leaf blade, short-leaved. Young plants have almost sessile. The lower leaves are twice pinnatipartite, long-leaved. The upper part of the leaf blades without pubescence, the lower is lighter, is covered with a light fluff that gives the sheet a grayish-green color.
In appearance, the vegetative mass resembles medicinal wormwood and inexperienced gardeners, these plants are often confused. Helps distinguish plants by their aroma. Wormwood has a bitter pure wormwood smell, and ragweed has a slightly wormwood-musty, suffocating, especially near the soil.
After 2 months from the appearance of seedlings, ragweed begins to bloom. Flowering lasts 2-3 months. Flowers unisexual, small, five-toothed. According to the color of the corolla, the flowers range from greenish, gray to yellow.
Male and female ragweed flowers are collected in separate baskets. Male stamen flowers are collected in baskets of 5-25 yellow flowers, which are formed into spike-shaped inflorescences located on the tops of the stems. Women's baskets are single-flowered. Collected 2-3 small baskets. They are located at the base of male inflorescences, sometimes in the axils of the apical leaves. Flowering is long and lasts from June to October, depending on the region. The optimum temperature for flowering and its duration is + 22 ... + 24 ° C. During flowering, plants form a large amount of allergenic pollen, which contains ragweed. The size of the pollen grain is several times smaller than the poppy seed.
Fruits of ragweed - achenes of obovate or nut-shaped, gray-greenish color with 4-6 spines. The fruits ripen no earlier than August. One plant during the growing season forms from 25 to 150 thousand seeds. Unripened seeds (even dairy maturity) also retain viability and germination. Once in the topsoil (4-5 cm), they can immediately germinate or germinate the next year. Seeds that fall into the 10-15 cm layer do not germinate, but remain viable for up to 40 years and under suitable conditions they germinate and begin to develop rapidly.
Ambrosia trifid and holobellate differ from wormwood by separate features of the external structure. In tripartite, unlike wormwood, the leaf blade has 3-5 shares. Three-part Ambrosia often clogs vegetables, pastures, prefers to grow and develop on fertile soils.
In hololtaceous ragweed, an underground rhizome with subordinate roots is developed that successfully overwinter in the soil and begin vegetation in spring. When divided into parts, each of them forms a separate plant.
Ambrosia Control Methods
The difficulty of fighting ragweed
In the life cycle, ragweed developed unique properties that help it survive in the struggle for living space:
- ragweed produces a very large number of seeds that remain viable for up to 40 years, and at any stage of maturation from dairy to full;
- Ambrosia propagates by self-sowing and only by seeds that need a resting state of 4 to 6 months, which is achieved by autumn digging with a turnover of the reservoir. In subsequent years, when it enters into acceptable environmental conditions, it emerges and successfully develops;
- improper mowing of ragweed (above the root neck) during the growing season contributes to increased growth and branching of the aerial mass;
- deeply penetrating the root root of ragweed - a great pump that provides the plant with moisture and nutrients;
- fast-growing biomass obscures the growth of other plants, and a "hungry ration" of nutrients without sunlight in the short term destroys them.
Ambrosia is such a dangerous weed that in the struggle for its complete destruction it is necessary to include both its physical destruction, and the use of chemicals (which is undesirable in dachas and adjoining areas) and biological extermination.
Methods of combating ragweed can be divided into several types:
- physical destruction;
- agrotechnical methods;
- use of chemicals.
The physical destruction of ragweed
The most acceptable and common method for suburban areas and surrounding areas is hand weeding. Mechanical destruction of the weed, which is primitively reduced to digging it up with the root (if it is not continuous thickets, but separate plants).
Multiple Mowing. With 1-2-fold mowing, the young plant forms from 5 to 20 young shoots. To deplete the weed, you need to carry out at least 5-6 mowing. Young ragweed mow in the phase of the onset or (in extreme cases) mass budding. Plants do not have time to form seeds, which even when underdeveloped already have the ability to germinate. A constantly mowing plant depletes and dies with the onset of cold weather.
Root neck cutting. If the plant is mowed above the root neck (the place where the root passes into the stem), then young shoots begin to develop on the segment of the stem, and the plant develops safely, and branched from the first days of a new life. If you cut off the floor of the root, then the rest will safely “work”, supplying the plant with water and nutrients. Cutting the root neck of ragweed is best done with a hoe, but you can also use a hand cultivator. With the correct implementation of this procedure, the number of treatments can be reduced to 3 per season.
Provocative watering and weed control in the white string or first green leaf phase.
Agrotechnical methods for the destruction of ragweed
The best agrotechnical method for the destruction of ragweed on the site is the method of crowding out weeds with other plants.
Artificial Tinning Method all free sites, including garden and berry, adjacent territories. You can use a mixture of cereal and perennial legumes, foxtail, alfalfa, fescue, beechless rump, rootless wheatgrass, sainfoin, etc. Overgrown grasses will literally strangle an annual weed. Formed natural lawns with a dense turf will clear the area of ragweed, and caring for lawn grass is much simpler than a grueling struggle with a “cheeky” weed.
Good result provides half steam field preparationusing siderates. For example, Sarepta mustard (Southern Scientific Center of the Russian Academy of Sciences) cleared the fields of quarantine weed.
Necessary correctly rotate crops in crop rotation and fulfill all the requirements of agricultural technology, which will gradually deplete stocks of germinating weed seeds, including ragweed.
Chemicals for the destruction of ragweed
The most radical method is to kill ragweed with herbicides. Recently, the market has replenished with new generation herbicides, which, destroying weeds, themselves decay in the soil in a short time to safe compounds for soil flora and fauna. Such substances include AmbroMag, Tornado, Hurricane Forte, Roundup, etc.
It is better to use herbicides in areas with ragweed and other weeds outside the local area - along roads, abandoned lands, vacant lots, etc. Radical measures are needed there to forestall the spread of ragweed seeds.
Remember! In the territories of settlements, pastures, while in the country, the use of toxic chemicals is prohibited.
Using herbicides, be very careful and careful, follow all the requirements on the packaging or other individual recommendations. Do not forget about sanitary measures of personal protection.
Dear Reader! We hope that our article will allow you to appreciate the insidiousness of ragweed, and the proposed methods for its destruction will give the desired result. We have no doubt that each of you has developed and uses its own methods of weed control without harming yourself and your family members, soil and cultivated plants. Share your secrets with us, which will help to develop new effective techniques and rid our land of harmful ragweed.