Crop production

Chapter V Weed plants and control measures

Plants not cultivated by man, but contaminated agricultural land, calledweeds.There are a lot of weeds, only about 1,5 thousand species are counted on the territory.

Cultivated plants of other types of isorts growing in crops of agricultural crops are calledweeds.

For example, weeds are winter crops in winter wheat, oats in wheat, etc.

Weed damage

Weed an enormous damage to agriculture. Less demanding conditions of growth, they are ahead of the cultivated plants in growth and development.

Absorbing moisture, nutrients, sunlight, weeds dramatically reduce the harvest, impede harvesting of field crops, their threshing, impair the quality of products.

They contribute to the reproduction of pests and the spread of diseases of agricultural plants.

Many peaches are harmful and even poisonous to livestock animals and humans. Pollen of ambrosia and pollen causes allergic diseases.

Impurities of creeping, buttercup, horsetail in hay and in pasture forage can cause animal poisoning. Melilotus officinalis, garlic, wormwood give an unpleasant taste to milk and butter.

Grains mixed with henbane seeds, cockle, stupefying chaff, and poisonous bitter make products of processing grain and feed unsuitable for humans and animals.

It is difficult to fight with weeds, because of cultivated plants, they are distinguished by very high fertility, long-term preservation of seed germination, a variety of propagation methods, ability to vegetative reproduction, and more early seed ripening.

Biological groups of weeds

Weeds are divided according to their biological characteristics: the method of nutrition, life expectancy, method of reproduction. According to the method of feeding, weeds are divided into parasitic(non-green plants) and non-parasitic(green plants) (table. 12).

Parasitic 'weeds are plants that have lost their ability to photosynthesis and feed on the host plant. Stem parasitic weeds stick to the stem of the host plant.

These include dodder(Cuscuta):clover,linen, field.

Root parasitic weeds are sucked to the roots of the host plant — this broomrape (Oro-banche)sunflower, hemp, cabbage.

Semi-parasites are weeds that have not lost their ability to photosynthesis, but are fed by the host host. These includerattling a big, ivan-da-Marya, a rack of teeth, mytnikbolotnyand etc.

All-parasitic weeds divide into perennial and perennial.

Classification of plants (A.I. Maltsev, 1926)

Young weeds

EphemeraPlants with a very short period of vegetation (45 - 60 days), capable of giving several generations during the season.

The most common type is wood louseor stars average(Stellaria media) from the family of Cloves, growing in damp places. This is a malicious weed and even spring grain crops. A single plant forms 15-25 thousand seeds.

Seeds are small, they retain their vitality in the soil for several years, but they do not germinate with great depth. Autumn leaves overwinter.

Yarovyevoryaki.There are early and late. The first ones are springing up and end the growing season of the pre-ripening of cultivated plants, the second ones are developing and mature after harvesting.

Spring weeds are one generation per year. The shoots that appeared in the autumn, perishing prizimovke. The most dangerous springfield -oatmeal(Avena fatua) Clogs cereals.

Seeds can easily fall off, but are poorly separated, especially from barley seeds and oats.

Cromeny, in crops are common: field-field(Spergula arvensis),mountaineer(Polygonum lapathifolium),radikapolovaya(Raphanus raphanistrum),fine white(Chenopodium album).

From late spring widely found:ordinary(Amaranthus retroflexus),bristles (mice) green(Seta-paviridis),kurai(Salsola rutenica),chicken(Echinochloa crusgalli).

Wintering weeds.These are juvenile weeds, which end their growing season with early spring shoots in the same year, and with late shoots capable of hibernating in any phase of growth.

Occur in crops of winter and spring crops.

Most common of them shepherd's bag(Capsella bursa pastoris), large field(Thiaspi arvense),vysilexinium(Centaurea suan us) et al

Winter crops.Plants that need for their development in low temperatures of the winter season, regardless of the time of germination. They spring up in the fall, wintering in the form of a rosette.

give seeds only next year. These weeds include: kosterrzhanoy(Bromus secalinus),battlefield (V.arvensis),field field(AregaSpica Venti).

Semenacostra fall into the seeds of rye and often contaminate its crops in the Non-Chernozem and Central Chernozem zones.

Biennial weedsPlants for the development of which requires two full growing season.

These include: donnyy yellow(Melilotus officinalis),white clover(M.

albus),helen black(Hyoscyamus niger),thistle-covered(Carduus nutans),cutter(Fulcaria vulgaris).

Donnic as a weed is common in Ukraine, the North Caucasus and in the Nonchernozem zone. Eaten by animals in large quantities, it can cause painful phenomena. Helen - weed

Types of weeds: name, description, photo | Construction portal

| Construction portal

One of the most important points for the care of garden beds, garden and lawn - the prevention and removal of weeds.

Methods of control depend on the type of weed plant, its biological characteristics and the place of growth.

Consider the main types of weeds and describe the methods of controlling their spread.

Harm and benefits of weeds

Weeds are called plants that "settled" on the site in addition to the cultivated crops. Fighting them takes away a lot of time and effort from summer residents. To date, more than 2000 weeds are known, including poisonous and harmful to animals - about 100 items.

No matter how hard we try, we cannot get rid of weed plants once and for all - they get to the site through various sources:

  • some weed seeds "sit" in the soil and expect favorable conditions for germination,
  • organic fertilizers - if the compost has not been properly processed,
  • poor quality seed,
  • the seeds are brought in by the wind, animals, people (on the sole of the shoe).

Weeds cause significant damage to agriculture and landscape design:

  • muffle cultivated plants and reduce their productivity,
  • release harmful substances into the soil,
  • absorb large amounts of nutrients and water,
  • create a shadow
  • can cause poisoning of pets,
  • are the focus for the development of diseases and pests of agricultural crops.

But not all so simple. Agricultural technicians note that some types of weeds are beneficial.

Weeds with strong roots break up soil compaction and loosen the soil, extract useful substances from great depth, which is not available to lawn grass and some garden crops. From such plants a good fertilizer is obtained.

Weed classification

All weeds are classified according to three main biological characteristics:

  • lifespan
  • breeding method
  • way of eating.

Depending on longevity, weeds are divided into young and perennial species.

Juvenile "weeds" multiply by seeds. This group includes:

  • ephemera - vegetation period less than one season,
  • Spring - the vegetation period is the same as that of annual garden plants; more often than the rest of weeds, cultural crops are clogged,
  • winter annuals - sprout in early autumn, litter the planting of perennial grasses and wheat crops,
  • biennial - full development cycle includes two vegetation periods.

Perennial weeds can grow in one place for up to 4 years. After the seeds ripen, the plant’s ground organs die off, and the root system continues to grow. Every year new stems grow from the underground part. Perennials multiply vegetatively or by seed.

According to the method of feeding, these types of weeds are distinguished:

  1. Non-parasitic weeds have an independent type of food and their development does not depend on other plants. The most numerous group.
  2. Semi-parasitic weeds have the ability to photosynthesis, but at the same time, partially feed at the expense of other crops - they stick to the ground organs or the roots of plants. Typical representatives: European flower belt, mistletoe, marianica field, marsh mytnik, late-toothed.
  3. Parasitic weeds - the plant has no green leaves, roots, is not capable of photosynthesis and feeds exclusively at the expense of another plant. Weed parasites are attached to the roots or stems of cultivated plants. This group includes: dodder clover, linen dodder, sunflower broomrape. Method of reproduction - seeds.

Weed plants in the garden: names, descriptions, photos

Pyrey creeping lives in the fields, gardens, gardens, floodplains, along roads. It has a deep root system and quickly spreads over the site.

The stem of the weed is upright, the leaves are flat, long with a rough surface.

Pyrei is very resistant to adverse conditions, it is propagated by rhizomes on almost any type of soil, a perennial plant of the grass family. It is necessary to get rid of wheatgrass, especially if you plan to plant potatoes.

If you do not fight with wheatgrass, the lawn can fully grow weeds: photo

Field bindweed (birch) - a perennial weed, enveloping the stems of plants. One plant can entangle up to 2 square meters of crop area. Berry bushes suffer the most from birch trees.

The length of the stem is up to 180 cm, the leaves are arrow-shaped, the fruit is a two-nesting box.

The branched roots of the field bindweed go to the ground to a depth of five meters, so it is very difficult to completely get rid of the plant - you will have to dig up the roots.

Garden purslane is an annual plant with a reddish thick stem and fleshy leaves. The length of the stem - about 60 cm, shoots of one plant can cover a significant area of ​​the garden. Portulac can be used for medicinal purposes and in cooking.

Mokritsa (starfish) - wintering annual, ephemer. Shoots of weed appear in early spring, and when the time comes for the germination of cultivated plants - wood lice grows into a solid green carpet. From this weed crops suffer carrots.

In the old days, woodlice predicted the weather for the near future. It was believed that if after sunrise sun-flowers did not rise or open, the precipitation should be expected during the day

Thyrum thrown back - spring early annual, characterized by very high fecundity.

Weed seeds are not afraid of mechanical effects and retain the ability to germinate for 5-40 years.

The plant has a high pubescent stem (up to 150 cm), ovate-rhombic leaves, flowers are collected in a dense paniculate inflorescence. Seeds can germinate from a depth of no more than 3 cm.

Hedgehog (chicken millet) - litters vegetables (sunflower, carrots, beets) at the beginning of their growth. In rainy years, it is able to completely silence sparse young crops.

The stalk reaches 120 cm in height, the leaves are broadly linear, pointed at the edges, the inflorescence is a panicle with spiny single-flowered spikelets, filled with seeds that look like millet.

Tenacious bedstrap - early spring annual. A distinctive feature - the trunk and leaves of weed literally cling to clothes.

A sturdy bedstraw appears on fertile, limestone-rich soils.

The horse's weed system is pivotal, the stem is tetrahedral up to 1 m high, there are small spines curved down on the ribs of the stem. The flowers are gathered in thick panicles, the flowering period is summer.

The shepherd's purse is a wintering annual, blooming from spring to late autumn. Seed viability lasts almost 35 years.

The height of the stem is about 20-40 cm, the leaves are pinnately dissected, the root is tap. White small flowers are collected at the very top of the stem, weed bloom continues throughout the summer.

During this time, the plant produces 2-4 generations (the seeds fall off and immediately germinate).

Yarutka field - an annual plant with characteristic rounded fruits with a cut at the top. The height of the stem - no more than 40 cm, the leaves are collected in the outlet and are located near the ground. During the flowering period yarutka gives up to 50 thousand seeds. The maximum depth at which seeds can germinate is 5 cm.

Sow thistle pink, better known as the field thistle - a common perennial weed plant that litters any crops. The height of the center can reach 1.5 m, the surface of the stem is prickly.

The leaf shape is lanceolate, there are spines along the edges. An adult plant has a strong root system, growing to a depth of 6 meters.

On the bends of the root buds are laid, giving the development of above-ground shoots.

The main source of clogging in a vegetable garden with a deadlock is a vertical root. When fighting against thunder, it is necessary to destroy the root system located at a depth of 60-70 cm

Lawn Weeds: Names, Descriptions, Photos

Bluegrass - an annual weed. At the beginning of growth, the plant imperceptibly, but over time the weed blooms and stands out with ugly spots on the lawn carpet. Bluegrass feels good on compacted soils in the lowlands. If weed out in time, it will not appear on the lawn for a long time.

Do not avoid the appearance on the lawn dandelions, the seeds of which are carried by the wind. Best dandelions "take root" on the young, rarely planted lawns.

A weed plant has fleshy roots, which contain a large supply of nutrients.

This must be taken into account when weed control - for complete destruction, more than one herbicide treatment with selective action will be needed.

A creeping buttercup is a perennial weed with a stalk creeping along the ground. The length of the plant is about 1 m, the leaves have a triple form. Buttercup multiplies seeds and vegetatively. Favorably develops in humid and under-lit places.

Moss, like buttercup, appears on damp soils in the lowlands. To combat it, the lawn should be regularly aerated and drainage ditches should be made. The height of moss is no more than 50 cm. If you do not deal with this weed, then it can completely displace the lawn cereals and lead to waterlogging of the soil.

The appearance of moss may indicate a "poor" soil composition, a lack of nutrients and an excessive level of soil acidity.

Plantain often grows on soil that has been re-compacted or trampled, or in places where moisture is stagnant. For removal of adult plants the special garden fork will be suitable. If the plantains have grown significantly on the lawn, then it is necessary to use herbicides of selective action.

Veronica filament settles on moist soil rich in useful elements. Plant height is no more than 12 cm, the stem is thin, the flowers are soft purple. Weed breeds shoots.

Clover is the most problematic weed that delivers a lot of trouble to lawn owners. A perennial plant with a height of 15-50 cm, root system - rod, leaves ovoid. The appearance of clover can signal a lack of nitrogen in the soil.

The active growth of clover can be provoked by potash and phosphate fertilizers introduced in spring.

Mar white - frost-resistant weed on the site, growing from early spring to late autumn. Plant height can reach 1.5 m.

The maximum depth at which seeds can germinate is 10 cm.

The plant must be removed before flowering, as one weed can produce about 500 thousand seeds with different shoots.

Common oxygen (hare cabbage) is a perennial plant with a strong root system. Weed grows in groups and easily "clogs" the lawn grass. Oxygen is very resistant to many chemicals, so the most effective way is to tear the weed from the root.

The presented photos and names of weeds will help to recognize and eradicate malicious pests in time.

Useful weeds on the plot

Not all weeds are pests; in the garden and in the garden you can also find useful wild plants.

Cornflower blue - healing seasoning in cooking. It is believed that the plant has a diuretic, analgesic, choleretic and wound healing effect.

Infusion of flowers helps with boils, eczema and conjunctivitis.

Cornflower dried inflorescences are used as a natural dye in cooking.

Meadow clover is credited with antiseptic and anti-inflammatory qualities. The plant is used in the treatment of atherosclerosis and dry cough. Spring salads are made from the flowers of clover and young leaves, and dried shoots are added while cooking the main courses.

Young nettle - a valuable gift of spring. It contains large amounts of vitamin C and carotene. The use of a decoction of nettle stimulates the metabolism in the body and promotes weight loss. Nettles are used when cooking soups, borscht, cooking meat, omelettes and other dishes.

Horsetail is a perennial plant in height up to 60 cm. It is used in the treatment of the bladder and as an antimicrobial agent.

Dry grass brewed, insist and drink before meals.

To improve blood circulation and alleviate conditions in rheumatic diseases, horsetail baths are recommended.

Highlander bird (knotweed) - one-year weed growing in gardens, parks, gardens and lawns.

Knotweed contains many biologically active substances: coumarins, flavonoids, essential oils, vitamins and phenol carboxylic acids.

The plant can be used as an antipyretic with colds or outwardly to accelerate the healing of wounds and ulcers.

Weed prevention

To deal with weeds in the garden and lawn will be much easier if they are not too much. For this it is necessary to carry out preventive measures.

Lawn care recommendations that reduce the likelihood of weeds:

  1. The lawn should not be cut too short. Young lawn need to cut a little, but often.
  2. Regular watering in dry weather. The lawn should not thin out after the summer, otherwise empty areas will quickly occupy the weeds.
  3. Cleaning the lawn with a rake prevents creeping weeds from growing.
  4. Top dressing will help to strengthen the lawn grass and will not allow weeds to force it out.
  5. Detection of diseases and pests. If it was not possible to protect the lawn, then the thinned area should be sown with fresh grass seeds before weeds appear on it.
  6. Any weed plant should be removed immediately, until it has grown bulk roots and is not ripe for seed.

Preventing the emergence of garden weeds:

  1. At the site it is necessary to allocate a fenced place under the compost pit, where during the season all the residues of weeds from the garden will be folded.
  2. In the autumn, after harvesting, it is necessary to dig up the garden, without breaking lumps. Many rhizomes of weeds will be on the surface and they will freeze out over the winter.
  3. In early spring, before planting vegetables, they re-dig and try to remove the remaining plant roots as much as possible.

Characteristics of the main types of weeds

Botanical systematics of weeds are classified according to the most important biological characteristics: the method of plant nutrition, longevity and reproduction.

According to the way of nutrition, weeds are divided into the following groups: non-parasitic, semi-parasitic and parasitic.

Non-parasitic weeds. These are ordinary plants with a developed root system. They are divided by life expectancy into two groups: juvenile and perennial.

Young weeds. They multiply by seeds (sometimes by parts of plants), have a life cycle of not more than two years. After the seeds ripen, the plants die off.

Young weeds are divided into several groups according to life expectancy and biological peculiarities: ephemera, early and late spring, wintering, winter and biennial weeds.

Ephemera- young weeds, or short-term weeds, which have a very short growing season. Over the course of one summer, these plants are capable of giving several generations and strongly littering the fields and crops.

A typical representative of this group is the starburst medium (or woodlouse), which has a very weak branched stem, lying on the ground or slightly rising. The starfish is a malicious weed that litters all fields, but it causes special damage to row crops and vegetable crops.

The vegetation period of this plant is about 40 days. The star sprocket average gives 15 ... 25 thousand seeds, in which the durability of preservation in the soil reaches 5 ... 8 years. Seeds germinate well from a depth of 3 cm.

When loosening the soil and precipitation shoots sprockets appear throughout the summer.

Spring early weeds
mostly litter cultures of early sowing time (oats, flax, etc.). Of this group of weeds, wild oats, chaff, quinoa, white mars, etc. are most widely distributed.

Wild oat is very similar in appearance to the cultured oats, but differs from the latter in that its grains easily fall out of the spike when ripe.

The oat reaches a height of 80 ... 120 cm, and each of its panicles can produce 40 ... 50 seeds. Wild oats ripen before grain crops.

Its grains are showered and when threshing grain along with them fall into the bunkers of combines and further into the granary. Oat grains are very difficult to separate from the seeds of cultivated plants.

The viability of the seeds of oats in the soil is maintained for 3 ... 5 years. In spring, most of the seeds germinate within 6 ... 12 days. For the germination of oats, a favorable depth of their occurrence is 5 ... 10 cm.

Spring late weeds
- a relatively small group of plants that differ in late germination of seeds with a steady warming of the soil to a temperature not lower than 16 ... 18 ° C and good illumination of plants in the first weeks after germination.

This group of plants includes the arboreal ragweed, an rykhovnik (or chicken millet), green bristles (mice), schiritsa, thorny bush, kurai (tumbleweed), etc.

These weeds litter mainly such late-sown crops as sugar beets, corn, potatoes, millet, buckwheat, etc.

Ambrosia polynnolistnaya quarantine plant, imported from North America. Weeds all plants, forms a large ground mass, greatly depletes and dries the soil.

Each plant of ragweed ambrosia produces up to 150 thousand seeds that remain viable in the soil for at least 10 years.

It is found in the North Caucasus, in the Astrakhan and Volgograd regions, Primorsky Krai.

Wintering Weeds begin their development in the fall. The emerged shoots form a rosette with leaves adjacent to the ground, and a well-developed root system forms in the topsoil.

With the onset of spring vegetation, the overwintered seedlings develop rapidly and bloom long before the winter crops enter the tube. These weeds form seeds in the first half of summer.

Often they develop as spring crops and bear fruit while harvesting crops. Due to the duality of the nature of the development, these weeds are called wintering.

Wintering weeds are the most well-known and widespread in our country: field field, cornflower blue, walking pole, cockle, shepherd's purse, field violet, chamomile, odorless, etc.

Winter weeds
- plants similar in development to winter cereals. These plants litter the winter bread and grass. Spring shoots of these weeds (rye fire, field fire, broomstick, etc.

) during the summer, they bush and form a vegetative mass, but are not capable of developing fruiting shoots. Most of their shoots appear in autumn. Overwintered shoots continue to develop and they have time to get rid of the grain crops before harvesting and then die.

Biennial weeds- plants for the development of which requires two full growing season.

Spring shoots of thistle, clover, black henbane, Eastern sverbigi and other biennial weeds during the first summer develop into a dense outlet with a deep rod root system, in which plastic substances accumulate. In the second year, the plants use them for further development and fruiting, and then die with the root.

Perennial weeds.
They are the most vicious weeds. The majority of these plants, in addition to repeated fruiting and seed propagation, also have the ability to multiply by rhizomes, root suckers and bulbs.

Rod root weeds
plants with elongated and thickened main root and limited vegetative reproduction. These include wormwood, dandelion, acid sorrel, common chicory, etc.

Creeping weed plants
breed stem shoots (mustache, whip, etc.), creeping along the ground and rooting at the nodes. From these weeds the creeping buttercup, the silverweed goose, the buddy ivy-shaped, etc. are most known.

Rhizome weeds
they reproduce mainly vegetatively with underground stems (rhizomes) diverging from the parent plant to the side.

In such rhizomatous weeds, such as sow thistle, creeping wheat grass, horsetail, gumai, pigtail, coltsfoot, rhizomes, growing in the soil, branch out, and some of their ends reach the earth's surface.

These ends develop into new plants.

Root weed plants,
they reproduce predominantly by the roots giving offspring, which during the growing season are formed from the buds laid in the roots.

The most important representatives of root-weeding weeds are field thistle, field sow thistle, creeping gorchak, field bindweed, etc.

In a short time, a large number of young shoots are formed from each of these plants, which strongly inhibits cultivated plants.

Semi-parasitic weeds.
They litter the winter rye by sticking to its roots. From this group of weeds, a spring rattle, notched serpentine, ovchanka, and marsh dune forest (Ivan - yes - Marya) are known.

Parasitic weeds.

They have completely lost their ability to photosynthesis and feed at the expense of the host plant, contact with which is carried out by special organs - suckers.

Parasitic plants completely lack leaves and developed root system. Depending on the place of connection with the host plant, stem and root weeds are distinguished.

Top representatives stem parasites - various types of dodder: clover, flax, plain, etc. These weeds affect clover, alfalfa, flax, hops, sugar beets and other crops.

The filamentous seedling of the dodder that emerged from the seed has no roots, and during the first few days with rotational movements it searches for the host plant. Touching this plant, a weed twines around its stem.

Suckers at the ends of the shoots dodder grow into the tissues of the host plant and suck water and nutrients out of it. The dodder has neither roots nor green leaves.

On her shoots only numerous pale pink flowers collected in a glomerulus develop. All types of dodder found in our country - annual plants. In the fall, their shoots die off. New plants grow from seed next year.

Seeds that have fallen to the ground and lain in winter germinate at the end of spring, when other plants have more or less developed, otherwise there would be no suitable food for the parasite.

Root parasites include various types of broomrape, which parasitize on the roots of sunflower, tomato, tobacco, hemp and other plants. Contagions multiply by seeds germinating on the soil surface.

At the seedling broomrape at one end remains the seed coat in the form of a "cap", which is the top of the stem. Its opposite end grows into the soil and grows, describing a helix.

As soon as he meets the root of the host plant, the broomrape seedling sticks tightly to this root, after which the seedling begins to thicken and outgrowths appear on its surface, resembling warts.

The rest of the seedling carrying the “cap” dies off. The warty body releases the papilla, which grows into the root tissue of the host plant and begins to suck nutrients out of it.

Soon a kidney is formed on the surface of the warty little body, on which the stem of the parasite grows and flowers later appear on it and seeds are formed.

Basic Agronomy

By life expectancy in this biotype can be divided into five subgroups:

  • ephemera,
  • spring weeds (early and late),
  • wintering weeds,
  • winter weeds,
  • biennial weeds.

Ephemera - These are plants with a very short growing season (1.5 - 2 months), capable of giving several generations in one season.

A typical representative of ephemeral weeds is wood louse, or star-sprout medium. It develops in moist, well-treated areas.

Its branching, almost creeping stems are capable of giving adventitious roots. One plant reproduces 15-25 thousand seeds and can bear fruit 2 times a year.

The seeds are small, but remain viable in the soil for 2 to 5 years.

Spring weeds divided into two subgroups: early and late.

Early spring weeds germinate in early spring and finish the development before harvesting of cultivated plants or simultaneously with their maturation. This development of weeds leads to severe clogging of both soil and seed.

Late spring weeds germinate with sufficient warming of the soil, so they slowly develop and mature together with late spring crops, their seeds fall into harvests.

Many of the early and especially late spring end vegetation in the post-harvest period, thereby clogging up the soil.

Spring weeds provide only one generation per year. By the early spring mary are white, Highlander bindweed, wild radish, common oats, etc. Of the late spring widespread: shchiritsa thrown back, blue and green bristles, kurai, chicken millet, etc.

To combat these weeds, it is important to know the length of the dormant period of the seeds and the time during which they retain their viability. Most of the seeds of spring weeds do not germinate in the fall; this usually occurs after overwintering in the soil or in a granary.

The main methods of dealing with spring weeds (early and late) are:

  • cleaning seed,
  • thorough pre-sowing tillage,
  • thickened sowing of winter crops, spring crops,
  • timely care (harrowing winter crops, spring crops, tilled crops, inter-row tillage treatments),
  • stubble stubble with compulsory autumn plowing after weed germination,
  • use of herbicides.

Wintering Weeds with early spring shoots end growing season in the same year, and with late shoots able to winter in any phase of growth.

After overwintering, the weeds end vegetation early, so their seeds fall mainly into the soil.

Such biological features allow weeds to grow successfully in winter and spring crops.

The group of these weeds includes: blue cornflower, shepherd's purse, trecherbernik odorless, field yarut, larkspur, and others.

For the destruction of hibernating weeds, timely peeling of stubble followed by autumn plowing, spring harrowing of winter and spring crops is especially important. Pre-sowing treatment of crops can destroy the outlets of overwintered weeds.
Most wintering weeds can be destroyed by herbicides.

Winter weeds on the development cycle are similar to winter bread. For them, overwinding is mandatory. They multiply only by seed.

Regardless of the time of germination, winter weeds produce the stem, flowers, fruits and seeds only the following year. According to biological features, these are weeds of winter crops, mainly rye.

Of winter weeds, rye and field fire, blizzard, etc. are the most common.

Measures to control juvenile weeds include stubble stubbing following the harvesting of crops with disc stubblers to a depth of 4–6 cm in wet areas and 10–12 cm in dry ones.

Peeling destroys growing weeds and provokes the germination of seeds embedded in moist soil.

After the emergence of weed shoots (after 1.5 - 2 weeks), they are destroyed by subsequent plowing.

Biennial weeds undergo a full development cycle in two years. During the first year, the plants form rosettes of leaves or short stems. During this period, the root system goes deep into the ground.

The following year, in spring, the plants grow rapidly and produce seeds in the summer. Typical biennials germinate in the fall, bear fruit only after the second wintering. This group includes medicinal and white clover, black henbane, eastern sverbig, velcro, etc.

However, in the southern areas some. Biennials sprouted in autumn develop as winter crops, i.e. they form seeds for the next year.

The main measures to combat biennial weeds are aimed at cutting the root system with dumpers or plows with coulters during the fall treatment and systematically mowing on non-arable lands.

This group includes those weed plants that live for several years (4 - 10 or more) and annually form seeds and organs of vegetative propagation.

Annual vegetative resumption or reproduction perennial weeds is due to renal formed on the root neck (with tap weeds), the nodes rhizomes (rhizome) for root shoots (weed forming), tuber (tuber), on aboveground creeping shoots (creeping) and t The property of perennial weed plants to multiply not only by seed, but also vegetatively makes them more harmful.

Rod weeds in the first year of the growing season, they form a rosette of leaves from seeds and form one taproot that extends into the soil to a depth of 1.5-2 m.

Vegetative renewal comes at the expense of the kidneys, which are laid annually on the root collar, which is drawn into the soil to a depth of 6 - 12 cm.

Rodroot weeds include: wild chicory, acid sorrel, bitter wormwood, plantain lanceolate, etc.

These weeds reproduce mainly by seeds, since they have a limited capacity for vegetative reproduction. They are weeds of grain, forage and vegetable crops, are found in gardens and meadows.

In all root-weeds, the upper part of the root collar, which is cut off during processing, is able to take root and give rise to new plants.

An effective measure of weed control is tillage of the soil with a cutter or flat-cuts to a depth of 10 - 12 cm with subsequent harrowing. This allows you to remove the root of the neck on the surface of the soil, where they dry out and die.

In addition, the struggle can be carried out during the main tillage with a plow (25 - 27 cm) with a skimmer (8 - 9 cm), cutting the rods in two places and deeply plowing them.

Mochroot weeds vegetatively renewed from the tillering node buds. They are characterized by particleing - the splitting of the maternal individual into several parts, the fragments, capable of giving adventitious roots and thereby prolonging the life of an aging maternal plant.

Typical representatives of this group are caustic buttercup - a poisonous weed of wet meadows and a large plantain found in crops of perennial grasses, especially in fallow lands. Bovine weeds reproduce exclusively by seed.

Measures to combat them are correct tillage, especially peeling and autumn plowing, land reclamation work on draining wet places, and lime application.

Methods and methods of weed control

Non-parasitic plants

This is a small group of autotrophic weed plants that synthesize organic substances from inorganic in the process of photosynthesis. They have a well-developed aerial part and root system. The classification of non-parasitic weed plants by life expectancy is as follows: juvenile (one- and two-year-old) and perennial.

Perennial Weeds

These are plants that have a lifespan of more than two years, they multiply both vegetatively and by seed, and bear fruit many times during life. After the seeds have ripened, perennial weeds die only above-ground organs, and the underground (bulbs, tubers, roots, rhizomes) retain their viability. Every year, new shoots grow from the underground organs, forming stems, flowers and seeds. If we talk about the method of reproduction, the perennial weeds are divided into two subgroups - poorly propagating vegetatively or not growing at all vegetatively, and propagating mainly vegetatively. Typical representatives of perennial weeds are field bindweed, field mint, garden billow, creeping couch grass, horsetail, bitter wormwood, dandelion, coltsfoot.

The classification of perennial weeds by biological groups is as follows:root-rootstocks, rhizomatous, root-root, raceme, tuberous and bulbous, urinary follicle and creeping.

Root sprinklers weeds are rather dangerous perennials that are endowed with a pivotal, powerful, deep-rooted root. From the root, the lateral roots, on which there are regeneration buds, diverge radially, mainly vegetatively, with adventitious buds on the roots and, to a lesser extent, seeds. Representatives of this type of perennials - field sage, field sow thistle, small oxaloaceae, common colza, creeping bitter.

Rhizomatous Perennial weeds are endowed with underground vegetative reproductive organs (rhizomes), which develops very much, and they are placed in the soil at different depths. The rhizomes are quite tenacious, they contain a supply of nutrients. They reproduce mainly by vegetative adventitious buds on underground stems and, to a lesser extent, seeds. Representatives are wheatgrass, common finger, coltsfoot, millennial, alep sorghum.

Rodroot weeds are perennial plants that breed by seeds and have a tap root system. Sometimes damaged roots can produce vegetative shoots. Root one, thickened, extending deep into the soil, without rudimentary nodes, buds and leaves. The stalks die off annually and are renewed from the buds that are laid on the root collar or in the surface part of the stem. This species of perennial weeds is represented by wormwood, dandelion, curly sorrel, and chicory.

Brushwood - perennial weed plants with a fibrous root system and propagated by seeds. Root powerful wrist. The leaves and stems die off every year, and new ones are born in their place next year. Representatives of the brush root are a caustic buttercup and a large plantain.

Bulbous weeds have a bulb that serves to accumulate organic matter, multiply vegetatively, modified underground thickened stems. The bulb consists of a flat, strongly shortened stem-bottom on which thick scales develop, and in the center of the bulb are kidney-babies. The representative is a round onion.

Tuberous weeds - perennials with tubers, which are the organs of their vegetative propagation. The representative is Chistele marsh.

Creeping - perennial weeds that have above-ground creeping vegetative organs (stems) - something between a flower stem and real underground rhizomes that are intended for vegetative reproduction. In the nodes of the stems there are buds and leaves. Vegetative shoots are formed from the buds, which create their own independent root system. Representatives of creeping weeds are cinquefoil goose, creeping buttercup, ivy-shaped budr.

Parasitic plants

In the course of evolution, parasitic weeds have lost their ability to photosynthesis, and their nutrition occurs at the expense of the host plant by special organs-suckers or hausters. On the stems of plants there are reduced leaves-scales (without chlorophyll), which protect generative shoots in the early stages of their development. Parasitic weeds are propagated by seeds. Parasitic plants are divided into root and stem with respect to the attachment point of the parasite to the host plant.

Parasitic plants with thick simple or branching stems, with scaly leaves of brown color. Flowers are collected in a simple ear. A new young sprout develops from the seeds, it does not immediately rise to the surface of the soil, but remains in it by that time until it finds the necessary root of another host plant into which it is embedded and forms a thickening on it - a growth. Soon the stalks of the parasite make their way from this growth, and the stalks of the cultivated plant gradually dry out. Typical representatives of root parasites are broomrape hemp and sunflower broomrape.

These are annual and perennial parasitic plants that are completely devoid of their own roots and leaves. Only a filamentous stem matures from seeds. On the surface of the soil, he finds the one he needs to feed the host plant and sticks to it until the end of his existence. All parasitic stem plants develop well flowers, fruits and seeds. Representatives of parasitic stem plants - flax seed dodder, field dodder, clover dodder and others.

In conclusion, a schematic complete classification of weed plants is presented in the form of a table:

Maloletniki

Seed juveniles include species that multiply, spread from one site to another and are renewed annually at a given place with the help of seeds, fruits and sprouts called seed buds. They consist of five subgroups: winter, wintering, early spring, late spring and biennial weeds. Early spring weeds with a very long growing season and most of the later ones are at the same time harvesters, that is, weeds that continue to grow in the stubble after harvesting and, if they do not take measures, will grow strongly, giving a bountiful harvest of seeds.

Winter weeds in the Volga region a bit. These weeds develop normally and bear fruit only if they form seedlings in the fall. They are clogging up winter crops and perennial grasses, usually to such an insignificant degree that they do not do much harm.

There are a lot of types of wintering weeds, on the contrary, in the Volga region. Like winter crops, they can sprout in the fall, overwinter in the rosette phase (Fig. 1) or short shoots lying on the ground. In the spring, these weeds go out into the arrow, bloom and give seeds. Forming shoots in the springtime, wintering plants usually go straight to the arrow and then bear fruit. At emergence of shoots in the fall they litter winter crops and perennial grasses, having grown in the spring, - early spring.

In contrast to winter crops, wintering weeds clog up crops to a great extent, but, forming a small mass, they do not pose a serious danger.

Of the early spring weed plants, common oats, mar white, several species of quinoa, buckwheat, kuroi, katun and others are most widespread. They infest predominantly early spring crops.

The main representatives of the late spring weeds are mice, or gray and green bristles, millet of chickens, common mite, zhmindovidnaya and white. They are called later because they are springing up in the second half of spring and in summer simultaneously with millet and other late sowing cultures. Together with them they mature. These weeds are usually littered with late and tilled crops, causing great damage to them.

White grass, quinoa, and some others are among the early spring weed plants, and lately - schyrits, mice, chicken millet, and many others.

Two-year-old weeds, unlike those previously described, live for two years. In the first year of the seeds that are in the soil, they sprout, growing in impassive plants with a small above-ground mass and a thick root. At the root of the biennial reserves of nutrients are deposited. In many species of this subgroup, with the growth in thickness, the root simultaneously decreases in length, drawing the bases of the stems into the soil. Before leaving for the winter, the elevated organs and the thin feeding roots most often die. Only the thickened part of the root, in which nutrients have accumulated, and the base of the stalks that carry the buds and are usually immersed in the soil, remain alive. In the second year, the root system is restored, and fruitful shoots grow from the buds. After seed ripening, the whole plant, together with the root and aboveground organs, dies off. Biennials in mass quantities appear in the fields only in some particularly favorable years and breed here only with a low level of agricultural technology.

A separate subgroup of juveniles includes weeds-parasites. They stick to the stems (dodder) or the roots of cultivated plants (broomrape) and suck the juices out of them. In the Volga region, sunflower broomrape is the most widespread, causing great harm to sunflower crops. Tobacco, tobacco, hemp, melons and many garden crops are affected by the same sunflower as well as branched broomrape, characterized by smaller size and greater branching. The latter goes to crops from wild and weeds: wormwood, cocklebur and others.

From field dummies in the Volga region one can find clover (it is ordinary and small-seeded), thin stem, large-seeded (American, field), flaxseed, pepper and European. The first two species most often affect alfalfa and clover, the third, moreover, potatoes and melons, the fourth - flax, less often camelina and clover. Pepper and European dodders grow in the wild, but often go to cultivated land, affecting alfalfa, potatoes, vegetables, berries, bushes and trees.

Gardens, berries and forest plantations are harmed by tree dodders (one-column and hoppy). Their characteristic features are cord-shaped stems and large seeds. Both species in the wild state grow on different shrubs, from which they can move into gardens and plantings.

Tuberous vegetative juveniles live one year. On the roots of these plants, and in some of the rooted stems, tubers grow, on the above-ground organs - seeds.After the weeds die off, the tubers and seeds remain in the soil, which are their buds, providing annual seed and vegetative reproduction, distribution and renewal of the species. These weeds do not have much harm to crops.

Of bulbous vegetative youngsters, onion, or field garlic, represents a rather great danger. This is a typical annual winter plant that forms above-ground parts in autumn and fructifies the following year. It propagates, spreads and renews it with the help of seeds and onions. Bulbs in the amount of 10-15, rarely 30-50 grow on short, short-lived shoots extending from the bulbs of the parent plant. After insemination, the parent plant dies off along with the entire root system and shoots. Child bulbs are saved. As a result of the withering away of the maternal shoots, they become separated from each other and form independent plants the following year.

Perennials

Rodroot weeds usually grow on young fallows, penetrating the fields only with a low level of agricultural technology. They develop as follows. After the emergence of a seedling (the first year of life), the root of them begins to grow in thickness and at the same time in the area of ​​thickening shortened. This property is called contractile ability. As a result, the cotyledon node, and with it the bases of the shoots with their lower nodes are drawn into the soil. The following year, the plant resumes its above-ground parts from the buds, sitting in the axils of leaf scars of stem organs drawn into the soil. Most root-root plants cannot grow from the roots.

Shoots grown from buds sitting on underground stem organs produce seeds and then die. In subsequent years, renewal occurs in a similar way. The main root continues to shorten all the time, drawing more and more above-ground parts into the soil. As a result, a strongly branched multi-headed rhizome is formed, consisting of a number of bases of shoots sitting on top of each other and incorrectly called the root collar.

Over time, the main root ages and stops shrinking. The bases of the shoots, drawn into the soil, also grow old. As a result, after the main root loses its ability to contract, the renewal buds gradually begin to get closer and closer to the surface. When the place of their laying will be above the surface of the soil, the herbaceous plant dies. Only rod-shrubs - trees, or God's tree, and others continue to live.

Having ceased to shorten, the main root begins to die off. Instead, water and ash elements from the soil absorb the younger side roots. In them, the plants lay off spare substances. These roots are shortened in length and can eventually sever the main root along. This phenomenon is called partitioning. It creates conditions for pulling in aboveground organs into the soil with lateral roots and, as it were, rejuvenates the plant, significantly increasing its life expectancy.

Rhizome weeds (Fig. 2 and 3) multiply, spread and renew with the help of rhizomes and seeds. Rhizomes are perennial underground stem organs with internodes and nodes. The nodes of young rhizomes are triangular scale-like leaves, in the axils of which sleep buds sit. Over time, these leaves dry out and fall off, with the result that in dicotyledonous plants, the old rhizomes are very similar to roots. They differ from them in the presence of leaf scars and anatomical structure.

A distinctive feature of root-weeding weeds is the ability to grow from their underground organs, to form root shoots on them. These weeds are propagated with the help of seeds and underground parts (roots and rhizomes).

The most dangerous and resistant weed from the group of root shoots is creeping gorchak. His grass is poisonous. The field bindweed stands in the second place for stability, the pink and yellow sow thistles in the third, and the Molokan blue in the fourth (Fig. 4). These five species are the most dangerous and difficult to eradicate weeds of crops, especially on irrigated lands.

The root system of all root-weeding is difficult. It consists of vertical maternal and affiliated, as well as horizontal and feeding roots. In addition, it includes rhizomes and young shoots (Fig. 5).

On virgin soil, long-term deposits and in the perennial grasses of recent years due to the large compaction of the soil and the rapid drying of its bindweed, sow thistle and Molokans do not form horizontal roots.

All the underground parts of the root-emitter bear the thin feeding roots. More of them are available on the roots, less - on rhizomes and young shoots. Buds that give rise to young shoots (shoots), can be laid almost all along the roots and rhizomes. The greatest number of them grows in places of cut or natural dying, as well as where the horizontal roots become daughter vertical (at the bends). The biological grouping of the most important weeds of the arid Volga region is shown in the table below.

Since according to the biological classification, weeds that have similar peculiarities of reproduction, distribution and renewal are combined in each biogroup, their specific agrotechnical measures are necessary to destroy the representatives of each such group.

Watch the video: CROP PROTECTION (October 2019).

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