Plants not cultivated by humans, but accompanying the planting of crops, are classified as weeds or weeds. Some of them enter agricultural land from the environment, with seeds, and are carried by animals and birds.
All weeds negatively affect the quantity and quality of the crop, reducing it by 10 - 50%. According to the structure of the seed of angiosperms, monocotyledonous and dicotyledonous weeds are distinguished. The presence of two seed lobes in representatives of the dicotyledonous class provides their seed with a large supply of nutrients, which in turn gives a more powerful growth of both the root and the ground part of the stem.
When seeds germinate, dicotyledons give a stem with two germinal leaves (according to the number of lobes). A true leaf begins to form from a bud located between them. In monocots, as a rule, real leaves come out immediately. Also, most dicotyledonous weeds have a powerful taproot that extends to a sufficient depth. In order to timely carry out agrotechnical measures to combat weeds of the dicotyledonous class, we will consider typical representatives characteristic of most regions.
- Annual and biennial dicotyledonous weeds
- Perennial dicotyledonous weeds
- Dicotyledonous weed control measures
Annual and biennial dicotyledonous weeds
- Blue cornflower is a weed with a stem up to 90 cm high, germinates in May, blooms in June - September. The flowers of the cornflower are blue, blue, purple. The seeds are very small, ripen in a large amount, up to 1500 per flower. Seeds remain dry germinating for 3 to 10 years. Blue cornflower infests, as a rule, crops of cereals.
- Highlander pochechuyny is a powerful plant more than a meter in height. The flowers are pink, greenish-pink, collected in long clusters. The mountaineer is even more fertile, yields up to 3000 seeds with a maximum viability of up to 10 years. Accompanies the planting of vegetable, oil, leguminous plants.
- Euphorbia - sungazer - is a strong plant up to half a meter high, with elongated leaves and a powerful well-developed root. Germinates in May, blooms all summer. The low germination of seeds is compensated by their huge number. Prefers to grow among cereals, legumes, forage crops.
Also ubiquitous annual dicotyledonous weeds include:
- sow thistle
- shepherd's bag
It should be remembered that dope, nightshade, henbane are dangerous poisonous plants.
Perennial dicotyledonous weeds
Dandelion officinalis is a ubiquitous plant, elongated leaves are collected in a basal rosette, the flowers are bright yellow, the seeds are easily carried by the wind. Found in garden and forage crops.
Wormwood is a powerful, tall, shrub-like plant. Germinates in May, blooms in July - August. Able to germinate from a depth of up to 10 cm. Yields several tens of thousands of seeds. It infests cereals, legumes, fodder crops, and garden crops.
Euphorbia vine is a weed that reproduces not only by seeds, but also by root suckers. Even a small remnant of the root makes it possible for milkweed to grow over the entire territory of the site. It accompanies almost all garden crops.
This group of weeds also includes:
- big plantain
- field thistle
- mouse peas
- creeping clover
- field buttercup
- creeping buttercup
The vigor and high fertility of weeds from the dicotyledonous class can not only reduce productivity, but also negatively affect the resistance of cultivated plants to diseases and pests. Therefore, their timely removal from the site is required.
Dicotyledonous weed control measures
Mechanical measures - are to remove weeds, their underground and above-ground parts. This can be done both manually, in small areas, and with the help of hand tools:
- root removers
- flat cutters
On areas up to one hectare, it is advisable to use motoblocks with
special attachments. Covering the row spacing with an opaque material will significantly reduce the amount of weeds on the site.
Chemical methods - cultivation of agricultural land with herbicides that are detrimental to dicotyledonous weeds. The soil is treated with soil herbicides before sowing, or before the germination of seeds of cultivated plants or in the fall, after harvesting. Penetrating to a depth of several centimeters, they destroy the seeds of weeds before they germinate. The following drugs are used against dicotyledonous weeds:
Postemergence herbicides can be divided into continuous and selective herbicides. Continuous chemicals destroy, as a rule, weeds and cultivated plants. These include:
- Lontrel 300
- Lapis Lazuli SP
It is worth saying that, subject to the recommended concentrations and application rates, modern herbicides do not harm human health. Sometimes it is very difficult to fight dicotyledonous weeds only by mechanical methods, because their seeds do not lose their germination for ten years, but the choice of methods for controlling them remains with the gardener.
Video about weed control on the site: