In 2020, employees of the "August" company, a well-known Russian pesticide manufacturer, conducted large-scale demonstration tests of means to combat Sosnovsky's hogweed. Variants of mixtures with selective soil herbicides showed a positive result in achieving the "tinning effect" - replacing hogweed foci with natural grass vegetation. Long-acting herbicides, which retain their activity in the soil, prevent the re-development of the pest plant, while glyphosate-containing preparations traditionally used against hogweed destroy it and decompose in a short time, and new shoots of weeds appear in the same place. Demonstration tests will continue in 2021: they are designed to show as broadly the results of the use of improved protection schemes against hogweed.
The specialists of the herbicides department of the industrial direction of the "August" company note that the interest of customer organizations in purchasing herbicides with a long-term effect against Sosnovsky's hogweed is growing. Usually, to combat a plant pest in Russia, preparations based on glyphosate were used - inexpensive and easy-to-use systemic herbicides that can penetrate into plant tissues and cause the death of green mass, but do not have a prolonged action.
“If hogweed has been growing on the site for a long time, then in the upper and deeper layers of the soil there is a large amount of its seeds,” notes Ivan Duborezov, sales and technological support manager of the herbicides department of the industrial direction of the August company. - To cope with them, it is necessary to use drugs, the active substances of which retain their activity in the soil for a long time. Treatments are effective in the spring, in the early stages of growth (up to 35-40 cm) - when spraying, the working solution of the preparations gets on the weed and the soil, affects the seedlings, inhibiting their development. "
In addition, glyphosate is a general destructive herbicide, while many drugs act selectively - for example, only on dicotyledonous plants. In this case, they cope with the cow parsnip, at the same time not affecting the cereal grasses. There is a "tinning effect": the cereal grass completely covers the areas where the hogweed previously grew, and the formed sod makes it difficult for its seeds to germinate further. Ivan Duborezov states: although new methods and preparations are more effective, many customers are not yet ready to refuse glyphosate-containing products because of their affordability. But when combined with selective herbicides that have a soil effect, good results are also achieved: when the action of glyphosate ends, the selective herbicides continue to work, allowing the hogweed focus to overgrow with cereals.
In 2020, the specialists of the herbicides department of the industrial direction of the "August" company conducted demonstration tests of drugs to combat Sosnovsky hogweed in the Leningrad and Moscow regions. Thus, in May, in the Leningrad Region, they were carried out on land plots in the buffer zone of the main gas pipelines of OOO Gazprom transgaz Saint Petersburg. For weed control, two tank mixes of the following products were tested:
1. "Tornado 540" (potassium salt of glyphosate acid, 540 g / l) + "Magnum" (metsulfuron-methyl, 600 g / kg) + "Adyu" (an adjuvant that provides an increase in the area of plant coverage with a working solution and the rate of drug penetration into plant).
2. "Gorgon" (MCPA acid, 350 g / liter + picloram, 150 g / l) + "Tornado 500" (isopropylamine acid glyphosate salt) + "Soylent" (hard water softener).
Both options showed high efficiency - the hogweed died in the areas of their application, no new shoots of the weed appeared. The preparations "Gorgon" and "Magnum" have soil activity; in addition, these are selective herbicides - they suppress dicotyledonous weeds without affecting cereal grasses. The visual effect of using the "Gorgon" on the hogweed in the form of deformation of the stems and leaves was noticeable already a day later, in the case of the "Magnum" it appeared two weeks later, but in the end the hogweed was destroyed in both plots.
In addition, in June 2020, demonstration tests of drugs were carried out in the technical right-of-way on the Moscow Railway (a branch of Russian Railways). The results of the application of various tank mixtures of herbicides were shown at once on five sites. Due to the restrictions caused by the spread of COVID-2019, these tests began later than planned: the hogweed had already grown up by June and was in the initial stage of budding (with a plant height of about 90 cm). Nevertheless, the weed was exterminated in all areas. The effect of tinning by natural grass vegetation was most pronounced in the area where a mixture of Tornado 500, Gorgon and Soylent was used: hogweed foci were overgrown with grass by mid-September.
“In 2021,“ August ”is conducting new, even larger-scale demonstration tests on the territory of the urban district of Mozhaisk in the Moscow region,” says Ivan Duborezov. - We are testing seven tank mixes at once. Their composition was developed by specialists of the industrial herbicide department in cooperation with the "August" founder of the development of protection schemes against hogweed, leading employee of the company Vitaly Vladimirovich Isaev. We plan to invite representatives of municipalities and organizations involved in the fight against hogweed in the Moscow region to the demonstration sites and visually familiarize with the results of the experiments.
As the experts of the company "August" note, effective schemes for the destruction of Sosnovsky hogweed should be spread wider: the long-term effect of their use contributes to more rational spending, in particular, budget funds, which can be used not for annual processing of the same plots, but for exemption from weed additional territories.