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Plants that accompany crops but are not cultivated by humans are called weeds or weeds. Many of them are carried by birds and animals or enter the soil along with the seed.
Weeds adversely affect the quality and quantity of the crop. Weeds are divided into annuals, biennials and perennials. They are also monocotyledonous or dicotyledonous, which is determined by the structure of the seed. Perennial dicotyledonous weeds have a more stable root system, and therefore receive more nutrients. It is very difficult to deal with such weeds.
In order to carry out all agrotechnical measures aimed at combating weeds in time, we suggest that you consider a list of dicotyledonous weeds with photos and names, to which a brief description will be attached.
Annual and biennial weeds
In the fight against annual weeds, it is important to prevent their reproduction through seeds. But to avoid this, it is important to know how and when weeds develop. Below we will consider the most common types of dicotyledonous annual and biennial weeds.
Cornflower blue
A weed with a stem of medium height – up to 90 cm. It sprouts in May, and the flowering period falls on June – September. Blooms in blue, blue and purple. From one flower of cornflowers, up to 1,5 thousand seeds usually ripen.
Seeds can be dormant in the ground for ten years and germinate under favorable conditions. Crops of cereals are especially affected by cornflowers. Belongs to the class of cereal weeds.
Persicaria maculosa
This is a super productive weed. From one flower about 3000 seeds are obtained with high viability – up to 10 years. The growth of an adult weed is 1 m. It usually accompanies the planting of legumes, oilseeds and vegetable plants.
Milkweed
This weed is also called sungazer. The plant reaches a height of 0,5 m. The root system is well developed. Milkweed leaves are elongated. It blooms throughout the summer, the first shoots appear in May. As a result, a lot of seeds are formed over such a long period, and even with a low germination of the weed, with inaction on the part of the gardener, his possessions will very quickly become overgrown with milkweed.
Euphorbia usually grows among legumes, grains and fodder crops.
lowlands ogorodnıy
There are 2 types of thistle – field and garden. The list of troubles for summer residents includes precisely the second type of weed. The growth of this weed is 30–100 cm. The leaves are pointed, serrated, long, saturated green. The stem is hollow. Baskets of sow thistle flowers reach a diameter of 3,5 cm. Sow thistle reproduces due to the formation of root offspring.
Swan and mar
These weeds love loose fertile soil rich in nitrogen, with a slightly acidic or neutral reaction. Potato fields are the best place for them to grow. The height of the bush can be up to 1,5 m. The appearance of these two types of weeds is an excellent indicator of soil fertility.
Nightshade
The best growing conditions for this dicotyledonous weed are in row crops, vineyards and orchards. At the same time, nightshade does not take root in the sowing of cereals, provided that the field has a normal density of standing of cultivated plants.
With insufficient care for cultivated plants and plantations, the soil will be littered with nightshade seeds.
Perennial dicot weeds
Perennial weeds cause even more damage to crops than annuals and biennials. Cultivated plants become more vulnerable to disease and insect infestation. The most popular perennial dicotyledonous weeds are dandelion and sagebrush.
Dandelions
This weed can be seen on almost every lawn. Elongated dandelion leaves diverge from the basal rosette. A distinctive feature of the plant is bright yellow flowers that are very attractive to bees. The seeds are quickly dispersed by the wind. Dandelions grow in lawns, fodder and horticultural crops.
Sagebrush
This is a tall plant that looks more like a shrub. The first shoots appear in mid-spring. The flowering period falls on July – August. Even being under a layer of soil equal to 10 cm, the seeds can germinate. During the flowering period, tens of thousands of seeds are formed from one bush. These grassy and dicotyledonous weeds infest not only cereals, but also horticultural and legume crops.
How to deal with dicotyledonous weeds
There are two methods of controlling annual and perennial dicotyledonous weeds: mechanical and chemical.
Mechanical method
The bottom line is to remove weeds, both underground and above them. In small areas, this can be done by hand or using a root remover, chopper or flat cutter.
The fight against broad-leaved weeds in large fields is usually carried out by walk-behind tractors. If you cover the aisles with a special material that does not transmit light, then you can effortlessly reduce the number of weeds in the beds.
Chemical method
Chemical preparations called herbicides can be used to remove perennial and annual dicotyledonous weeds. Such preparations can be used before crops are planted or before germination. But to achieve the best result, it is better to treat the soil with herbicides after harvesting. These products penetrate the soil, due to which monocotyledonous and dicotyledonous weeds are destroyed, since their root dies.
To destroy dicotyledonous plants, drugs such as Command and Pioneer are used. There are two types of post-emergence herbicides: selective and continuous.
In a number of continuous herbicides:
- Sniper.
- Roundup.
- Hurricane.
Among the selective herbicides that destroy dicotyledonous weeds:
- Lazurite SP.
- Lontrell 300.
Conclusion
All recommendations for the use of the above preparations for weed control are indicated by the manufacturer on the packaging. If you follow these recommendations exactly, then the funds will not harm your health. Of course, the least dangerous is the mechanical method of cleaning the garden and lawn from weeds. However, this method is not always effective. In some cases, it is better to treat the land with herbicides in a timely manner, especially considering that the seeds of some weeds can be in the ground for at least 10 years and sprout after this time.