Soil samples for analysis. When is it necessary to do a soil test and how is it done? Comprehensive soil research

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When creating a new personal plot or reconstructing an old one, it is very important stage is to study the soil conditions of the existing territory. It is advisable to carry out this work before the design of the garden begins, in order to be able to improve the necessary soil characteristics.

This largely determines how the plants will feel in the new garden. It’s no secret that on a nutrient-rich, moderately moist, cultivated garden soil yields are significantly higher. In addition, some adjustment of soil conditions allows you to expand the range cultivated plants Location on. So let's talk about how to conduct a soil test on a newly selected or existing site.

A complete and very detailed study of soils can only be done in a laboratory. But every summer resident is able to carry out a simple independent analysis and draw conclusions sufficient for further work. As part of such a field study, the following is established:

1. Mechanical composition.

2. Degree of aeration.

3. Acidity.

4. Hydrological features.

5. Fertility.

All these qualities are largely interrelated and are considered as a whole. To determine them, you can use simple methods.

Analysis of soil texture

To establish the granulometric composition, take a small moistened lump of soil and roll it with your palms into a cord 2-3 mm thick, then roll it into a ring with a diameter of about 2 cm.

If you can’t roll up the cord—it falls apart in your hands into many particles—then the soil is sandy.

If you succeed in rolling the cord, but when twisting it into a ring it falls apart, then the soil is sandy loam.

If, when rolled, a strong cord is obtained, but the ring cracks in several places or breaks up into large parts, then the soil is medium loamy.

If the lump produces a strong cord that easily curls into a ring, only slightly cracking at the edges, then the soil is heavy loam.

If the cord curls up into a strong, smooth ring, then you have clay in your hands.

Determination of soil aeration

This indicator is especially important for heavy clay soils, in which, due to high density, reduced aeration is often observed. Without the use of instruments, this indicator can be determined by color. In the presence of oxygen clay soil acquires a characteristic red tint. In conditions of lack of oxygen, the substrate becomes bluish in color, reminiscent of cement dust or lake silt.

Such areas can occur only locally - in the form of limited islands or inclusions. Sometimes too wet ash-gray clay lies in a continuous layer in areas. The solution may be either to use drainage or to plant moisture-loving plants that will reduce the amount of water in the soil, which will promote better aeration.

Determination of acidity

There are many methods for establishing pH. If special devices and test strips are not available, then you can use other methods. Moreover, ready-made store analyzers determine only one type of acidity – actual. But for plants, potential and metabolic acidity are no less important. It happens that the test shows a neutral pH level, and the plants literally “burn”, which clearly indicates increased acidity soil.

A more informative field test is phytoindication - that is, determining a parameter based on the prevailing natural vegetation.

Very low pH indicators:

Buttercup, white grass, cotton grass, sphagnum moss, horsetail, small sorrel.

Indicators of weakly acidic substrates:

Anemone lutinica, zelenchuk, wood sorrel, willow-herb, dog violet.

Indicators of neutral soils:

Hemlock stork, green strawberry, Siberian hogweed, meadow foxtail, coltsfoot, soapwort, cinnamon grass.

Alkaline soil indicators:

Crescent alfalfa, chicory, steppe aster.

Determination of hydrological features

This indicator can be approximately determined when digging a pit in your own or neighboring areas. If groundwater are located close to the surface, there will definitely be water in the pit.

Without any measurements, you can independently determine hydrological conditions also from plants. They perfectly show the degree of moisture content of the substrate.

On a waterlogged substrate there is a lot of:

Wild rosemary, wild rosemary, meadow geranium, blueberry, snakeweed, marigold, marsh cinquefoil.

On moderately moist soils there is a lot of:

Lingonberries, Phrygian cornflower, meadow clover, hoofed grass, stone berries.

In dry habitats there are many:

Feather grass, cat's foot, sedum, bearberry.

Determination of soil fertility

This criterion indicates the level of content of main nutrients, primarily nitrogen. Phytoindication can also help any gardener out.

Phytoindicators of low fertility:

Cat's foot, round-leaved sundew, gorse.

Phytoindicators of moderate nitrogen content:

Veronica longifolia, river gravel, angelica, wood sorrel, swimsuit, bifolia, lungwort.

Phytoindicators of highly fertile, nitrogen-rich soils:

Fireweed, stinging nettle, bromeless brome, cinquefoil, raspberry, meadowsweet, meadowsweet, celandine.

Agrochemical soil analysis- an event carried out to determine the degree of soil supply with basic elements mineral nutrition, determining the mechanical composition of the soil, pH and degree of saturation with organic matter, i.e. those elements that determine its fertility and can make a significant contribution to obtaining a qualitative and quantitative harvest.

Talking about agrochemical soil analysis, first of all, we mean control of the content of certain components on agricultural lands and lands intended for growing any crops (farm lands, garden plots, summer cottages and much more).

Soil research carried out on pre-selected samples. In accordance with current regulations In the field of soil analysis and sampling methods, samples can be collected using the "envelope" method or the "grid" method.

Depending on the area of ​​the territory used and the type of analysis, the sizes of the laid sites also vary. To monitor the condition of agricultural land, for every 0.5 - 20 hectares of territory, at least one test site measuring at least 10mx10m is laid out. Wherein:

A homogeneous terrain cover involves sampling on sample plots of 1 - 5 hectares to determine the content of chemicals, structure and properties of the soil; sampling on sample plots of 0.1 - 0.5 hectares to determine the content of pathogenic organisms in the soil.

Heterogeneous terrain cover; sampling on sample plots of 0.5 - 1 ha to determine the content of chemicals, structure and properties of the soil; sampling on sample plots of 0.1 hectares to determine the content of pathogenic organisms in the soil.

Sampling scheme for agrochemical soil analysis looks like this: taking into account the above recommendations, a test site is laid out on the territory. Along the diagonals running from one corner of the site to the other corner, point samples of the topsoil are taken, the mass of which should not be less than 200 g. We mix the resulting spot samples with each other, thereby obtaining the combined sample we need. A pooled sample consists of at least 5 point samples taken from one sample site. The weight of one combined sample must be at least 1 kg.

Agrochemical soil analysis reflects the condition of the soil according to the following main indicators

- Main agrochemical indicators (6 indicators):

pH - soil acidity- this is a property of soil caused by the presence of hydrogen ions in the soil solution and exchangeable ions of hydrogen and aluminum in the soil absorption complex.

Soil organic matter- this is the totality of all organic substances in the form of humus and the remains of animals and plants, i.e. important component soil, representing a complex chemical complex of organic substances of biogenic origin and determining the potential of soil fertility.

Grading- the mechanical structure of the soil, which determines the relative content of various particles, regardless of their chemical and mineral composition.

Hydrolytic acidity- soil acidity, manifested as a result of exposure to hydrolytic alkaline salt (CH 3 COONa). Determining hydrolytic acidity is important when solving practical problems related to the use of fertilizers, liming, soil phosphorite treatment and other agrochemical methods.

Sum of absorbed bases- the degree of soil saturation with bases, shows what proportion of total number of substances retained in the soil are absorbed bases.

Nitrates- total content of nitric acid salts. These substances are hazardous to humans and can accumulate in products Agriculture due to excess nitrogen fertilizers in the soil.

- Macroelements:

Mobile phosphorus- form of phosphorus assimilated by plants (P 2 O 5). A source of food for plants, a carrier of energy. It is part of various nucleic acids, and its deficiency dramatically affects plant productivity.

Exchangeable potassium- a mobile form of potassium in the soil that plays important role in plant nutrition. Plays a significant role in plant life, affecting physicochemical characteristics plants.

Nitrate nitrogen- nitrogen contained in the soil in the form of nitrates, used by plants to form amino acids and proteins.

Ammonia nitrogen- nitrogen is an ammonia compound that is used by plants for the synthesis of amino acids and proteins.

Iron- an element involved in the formation of chlorophyll, being integral part green pigment. Regulates the processes of oxidation and reduction of complex organic compounds in plants, plays an important role in plant respiration, as it is part of respiratory enzymes. Participates in photosynthesis and the transformation of nitrogen-containing substances in plants.

- Microelements:

Cobalt- a microelement necessary not only for plants, but also for animals. It is part of vitamin B 12, the deficiency of which disrupts metabolism - the formation of hemoglobin, proteins, and nucleic acids is weakened, and animals become ill with acobaltosis, tabes, and vitamin deficiency.

Manganese- a microelement that takes part in redox processes: photosynthesis, respiration, in the absorption of molecular and nitrate nitrogen, as well as in the formation of chlorophyll. These processes occur under the influence of various enzymes, and manganese acts as an activator of these processes.

Copper- a trace element necessary for plant life in small quantities. However, without copper, even seedlings die. The gross content of copper in soils ranges from 1 to 100 mg/kg of dry matter.

Molybdenum- a microelement that plays an exceptional role in plant nutrition: it participates in the processes of molecular nitrogen fixation and restores nitrates in plants. With its deficiency, plant growth is sharply inhibited; due to disruption of chlorophyll synthesis, they acquire a pale green color (leaf blades are deformed and leaves die prematurely). Legumes and vegetable plants (cabbage, leafy vegetables, radishes) are especially demanding of the presence of molybdenum in the soil in an accessible form.

Zinc- a microelement involved in many physiological and biochemical processes in plants, being mainly a catalyst and activator of many processes. Lack of zinc leads to metabolic disorders in plants.

Nickel- a microelement that takes part in enzymatic reactions in animals and plants, necessary for the normal development of living organisms. Increased nickel content in soils leads to endemic diseases - ugly forms appear in plants, and eye diseases in animals associated with the accumulation of nickel in the cornea.

- Toxic elements:

Cadmium- one of the most toxic heavy metals is classified as hazard class 2 - “highly hazardous substances”. The source, which is in the soil, is industry.

Lead - heavy metal, which is highly toxic. The presence of elevated concentrations of lead in the air and food poses a threat to human health. Automobile exhaust accounts for about 50% of total inorganic lead.

Chromium- connection of the 1st hazard class; trace element found in trace amounts in living and plant organisms. Excess chromium in soils causes various diseases in plants.

The presence of chromium in soils (up to 50-70 mg/kg of dry soil) determines its movement along the food chain: soil - plant - animal - human. The main sources of chromium and its compounds into the atmosphere are emissions from enterprises where chromium and its compounds are mined, received, processed and used. Active dispersion of chromium is associated with the combustion of mineral fuels, mainly coal. Significant amounts of chromium enter the environment through industrial wastewater.

Mercury- highly toxic chemically resistant element. Refers to dispersed elements (rare). The amount of mercury released into the environment in the current century as a result of anthropogenic activities is almost 10 times higher than natural intake and amounts to 57,000 tons.

Arsenic- microelement. Referred to as dispersed elements. Arsenic is a trace element necessary for the functioning of living organisms. At elevated concentrations, arsenic has a toxic effect on living organisms. The content of arsenic in the soil determines its content in natural waters.

Benz-a-pyrene- a complex chemical compound related to the so-called PAHs (polyaromatic hydrocarbons). An element of hazard class 1, formed during the combustion of hydrocarbons, regardless of their state of aggregation (liquid, solid, gaseous). Is the most common chemical carcinogen environment, dangerous to humans, even at low concentrations, since it has the property of accumulation in the human body. In relation to the natural environment, and directly to its factors, we can say that the highest concentrations are in the air and soil. Given this, benz-a-pyrene is very easily transported throughout the food supply. Each subsequent level of the food chain is accompanied by significantly increased concentrations of the carcinogen.

Petroleum products- hydrocarbons, or more correctly, a mixture of them, which may include more than 1000 independent organic substances. Each of these compounds can be considered as an independent toxic substance. In practice, the assessment of pollution of a particular object with petroleum products is carried out in the following areas: the content of light fractions (considered the most toxic to living organisms and the environment, but due to their evaporation, they ensure rapid self-purification of the soil), the content of paraffins (relatively toxic substances, mainly affecting physical properties soil), sulfur content (determining the degree of hydrogen sulfide contamination of the soil).

- Bacteriology:

Coliform index- shows the number of bacteria of the E. coli group per 1 g of soil. Coliforms are saprophytes of the intestines of humans and animals. Their detection in the external environment indicates its fecal contamination, therefore E. coli is classified as a sanitary indicator microorganism.

Enterococcus index- a sanitary-bacteriological indicator characterizing the quantitative content of bacteria of the genus Enterococcus (p. Enterococcus) in 1 gram of soil, also known under another term - “fecal streptococci”.

Pathogenic bacteria, incl. salmonella- a sanitary-bacteriological indicator characterizing the quantitative content of bacteria in 1 gram of soil, capable of causing infectious diseases under appropriate conditions.

Agrochemical soil analysis is of no small importance. It promotes the adoption of expedient and thoughtful decisions that contribute to the organization of measures to increase efficiency and increase the fertility of the lands used. Specification of tasks for a particular type of cultivated crop will not take long and will allow you to get a rich harvest - the desired result of any farmer.

Selection of soil samples in natural conditions and their preparation for laboratory research are the main issue of the methodology, on which the result of all subsequent determinations depends. It is necessary to correctly designate places for soil sampling, which would allow identifying areas that are subject to the greatest contamination and, conversely, those that are good in their sanitary condition. To do this, one or more sites are selected near existing sources of pollution, and the other - in a place remote from them. The depth of soil sampling is determined depending on the nature of the soil, the task and type of laboratory research.

To determine the mechanical and chemical composition soil sampling is carried out at 3-5 points diagonally from an area of ​​25 sq.m. from a depth of 0.25 m, and if necessary - from a depth of 0.75 - 1 m and ],75 - 2 m. Samples are taken with a drill or shovel, mixed thoroughly and from the samples taken from each horizon, a single average sample is made for it weighing about 1 kg, which is placed in a jar with a stopper, a number is put on the label and sent to the laboratory with an accompanying document indicating the place and time of sampling, depth, meteorological features at the time of sampling and what should be determined in the soil.

In the laboratory, soils are weighed, mixed, sifted and, depending on the purpose of the study, analyzed in their natural form or in an air-dry state, for which the soil is dried in air at room temperature followed by additional sifting through a sieve with holes 1 mm in diameter. The analysis of natural, freshly taken soil begins as soon as possible, since significant changes may occur in the soil due to ongoing biochemical processes. If it is not possible to test the soil on the same day, you can store it in the refrigerator for several days or add preservatives.

For bacteriological analysis, soil samples in the amount of 200-300 g are taken with sterile instruments also at 3-5 points of an area of ​​25 sq.m., placed in sterile jars and an average sample is made from them. Samples are taken from the depth at which bacterial contamination is suspected. In populated areas, it is recommended to examine, first of all, the surface layers of the soil to a depth of 20 cm. From areas of irrigation fields, samples are taken at a depth of 20 cm. When studying the effects of soil pollution on groundwater and open reservoirs, samples should be taken at a depth of 0.75 - 2 m. In the latter case, a Nekrasov drill is used for this, and if it is not available, a hole is dug and samples are taken from each side with a sterile spatula or knife. When monitoring the disinfection of household waste using the soil method, soil samples are taken from a depth of 25, 100 and 150 cm, depending on the physical properties of the soil. Sterilization of instruments for taking soil samples is carried out at each new site by washing with water, wiping with alcohol and finally burning.

Jars with soil samples are closed with cotton plugs, wrapped in paper and bandaged. The jar is numbered, the necessary data is recorded (air and soil temperature, etc.) and immediately sent to the laboratory. If jars are not available, soil samples can be transferred in sterile plastic bags or sterile parchment paper. In the laboratory, the soil is poured onto paper sterilized in a drying cabinet, freed from roots, crushed stone, glass, etc., large lumps of soil are kneaded, mixed thoroughly, and a sample of soil is taken from here for research. If, upon delivery of the samples to the laboratory, it is not possible to begin bacteriological research, they can be stored in the refrigerator at 1-5 degrees C for no more than 18 hours, since changes in the composition of the microflora occur over time.

For sanitary-virological analysis, samples of the arable layer are first taken, since under natural conditions enteroviruses are adsorbed mainly by the upper layers of soil. According to G.A. Bagdasaryan, samples are taken separately from ridges and furrows from a depth of 0-20 cm, to determine the penetration of enteroviruses deep into the soil - at a depth of 50 and 100 cm. The sampling technique is similar to that used when taking samples for bacteriological research; therefore, the same soil samples can be used for both analyses.

Primary processing of samples should be carried out on the day of sample collection immediately upon delivery to the laboratory. It is allowed to carry out the analysis on another day, no later than 24 hours later, provided that the samples are stored in the refrigerator at A gr.C. Longer storage entails a drop in the titer of enteroviruses and the possibility of their isolation decreases.

For helminthological analysis, soil samples are taken separately from the surface and from a depth of 2-10 cm, since, depending on the depth, helminth eggs survive for various terms. From each plot of 50 sq.m. take at least 10 samples weighing approximately 100 grams in different places along the diagonal and from them average samples weighing about 1 kg are compiled separately for each horizon.

Soil samples are taken from the surface layers with a metal spatula, a tablespoon or a scoop, and from the depths - with a drill or shovel. Samples are collected and transported to glass jars with a stopper or in plastic bags, labeling the container and noting, as usual, the time and place of sampling, external conditions and so on. Upon delivery to the laboratory, soil samples, if they were not in glass jars, are poured into glass jars, mixed thoroughly and large particles removed. The analysis is carried out within the next few days; if this is not possible, then the samples taken are filled with a 3% solution of formalin in saline solution or a 3% solution of hydrochloric acid and stored in open banks at a temperature of 18-24 degrees C, stirring frequently to improve aeration. When the soil dries out, add clean water.

For radiometric analysis, soil sampling is carried out in accordance with the task. To determine radioactive contamination of the soil in a given area, several areas with an area of ​​approximately 50 sq.m. are selected. and in the middle of each of them on an area of ​​about 1 sq.m. remove the grass cover and cut out the soil for testing in the form of a piece measuring 10x10 cm, 5 cm thick. The sample is packed in an oilcloth or plastic material and sent to the laboratory indicating the place where the sample was taken, date, etc. Vegetation is taken in quantities of about 75 g and packaged separately.

For chemical analysis of soil, the “Methodology for measuring the mass concentration of mercury in soil samples using the method of flameless atomic absorption with thermal decomposition of samples” PND F 16.1.1-96 is used. At the same time, a methodology is established for measuring the mass concentration of mercury in soil samples by atomic absorption analysis (flameless atomic absorption method.)

To assess the mechanical composition of the soil, a Knopp sieve is used, consisting of a set of individual sieves with holes. various sizes– from 0.25mm to 10mm. Each hole size corresponds to a specific sieve size. A sample of selected soil (200-300g) is passed through Knopp sieves, resulting in particles remaining on individual sieves different sizes. By weighing the contents of each sieve and determining their percentage composition in relation to the weighed portion of the entire sample, its mechanical composition is approximately estimated.

According to N. Kachinsky’s classification, particles retained on a particular sieve are classified as a specific type of soil:

On sieves with 3-10mm holes - stones and gravel;

On sieves with 1-3mm holes - coarse sand;

On sieves with holes 1-0.25 mm - medium sand;

At the bottom of the sieve there is fine sand and dust.

For planting, full growth, high yields and effective use fertilizers, a gardener or gardener must know what kind of soil is on his site. Soil acidity largely depends on the presence and amount of lime. Neutralization of acidic soils (liming) is often simply necessary. In some cases, it is ignorance of what type of soil on the site that is the reason for low yields of vegetables and berries. A novice summer resident sometimes wonders why they scare us with acidic soil?

Soil acidity depends on the amount of lime (CaCO3). As you know, soils are strongly acidic (pH 3-4), acidic (pH 4-5), slightly acidic (pH 5-6), neutral (pH 7), alkaline (pH 7-8) and strongly alkaline (pH 9). (pH) is a measure of soil acidity. It can range from 0 (extremely acidic) to 14 (extremely alkaline). Most fruits, vegetables and other plants feel comfortable at a pH of 6-7, and some at neutral. Neutral soils are soils with a pH level of 7. Approximately the reaction of soils can be judged by the growing weeds, if they have not already been eliminated during the operation of the site. But there are other ways, which are discussed below.

The soil for analysis must be taken in several places and at different depths, and the reaction of the solution must be determined in an aqueous extract. To do this, pour water into a glass or plastic container, place the soil in a clean cloth, tie it and lower it into the water. (For one part of soil by volume - 4-5 parts of water). After 5 minutes, immerse a dry strip of indicator paper in the soil solution for 2-3 seconds. or apply a drop of this solution to it. Then take out the paper and immediately compare the acquired color with the scale. As a result, you get the pH value. If the soil is acidic, you can add ash or lime. To neutralize acidic soils, peat ash (0.5-0.7 kg/m2) can be used, as well as oil shale ash containing up to 80% lime. Wood and straw ash can be used on all soils except solonetzic soils. This alkaline fertilizer is especially suitable for acidic sod-podzolic, gray forest, bog-podzolic and swamp soils, poor in potassium, phosphorus, and microelements. It not only enriches the soil with nutrients, but also improves its physical properties, in particular soil structure, and in addition, reduces acidity. At the same time, more favorable conditions for the development of beneficial microflora, and as a result, plant productivity increases. The aftereffect of this fertilizer lasts up to 4 years.
If the soil on your site is clay or loamy, it is recommended to apply ash in the fall, and in the spring fertilizers are applied to sandy and dry soils. sandy soils. To increase efficiency, it is advisable to use wood and straw ash mixed with peat or humus as an organo-mineral mixture (1 part of the ash is mixed with 2-4 parts of wet peat or humus). This mixture allows you to evenly distribute the fertilizer over the area even in windy weather, and the plants better absorb the nutrients contained in it. Many gardeners use wood and straw ash not only as fertilizer, but also to combat diseases and pests. It can be used against gray rot of strawberries. During the period of ripening of berries, pollinate the bushes at the rate of 10-15 g of ash per bush. Sometimes pollination is repeated 2-3 times, but less ash is consumed - 5-7 g per bush. The disease decreases sharply or almost completely stops.
IN last years many amateur gardeners to combat powdery mildew currants, gooseberries, cucumbers, cherry mucous sawfly and other pests and diseases, the plants are sprayed with an ash solution: 300 g of sifted ash is boiled for half an hour, the settled broth is filtered and brought to 10 liters. For better adhesion, add 40 g of any soap. It is better to spray plants in the evening in calm weather. This treatment can be done twice a month.
If the groundwater in your area is located high enough, then the soil analysis is carried out on site; after rain, simply lower a strip of universal indicator paper into a small hole with settled water and determine the pH.

The most accurate results can be obtained by comprehensive analysis, which is offered by specialized laboratories. For this you only need to prepare the material, that is, the soil from your plot of land, for analysis, but this must be done correctly, since the degree of accuracy of the results largely depends on this.

A soil sample from the site should be taken before applying fertilizers and liming. In different places of the land you need to make holes to the depth of a spade bayonet or a little deeper. It is this depth that most plants need to freely accommodate and nourish the root system, therefore, the soil must be comprehensively examined in this area. In total, at least 15-20 holes should be dug, which will allow for greater objectivity of the analysis, and thus, at least 15-20 samples should be taken from 100 m2 of site area. Then, sequentially, from the wall of each of the pits you need to scrape off thin layer soil in the direction from bottom to top and put in a bucket, after which all samples are thoroughly mixed in the bucket. At least 1 kg received soil mixture put in plastic bag and close it tightly.

When submitting soil for analysis to the laboratory, indicate the characteristics of your site, location and the main purpose for which you intend to use it. land plot(growing vegetables, fruit crops or anything else). Based on the analysis obtained, you will be able to accurately determine in which nutrients and microelements the soil especially needs, what fertilizers need to be applied and what measures should be taken to improve the composition of the soil.

An important role in assessing soil quality is played by its appearance, by which you can quite accurately determine the structure, some internal properties and quality of the soil. One of the most important external signs soil is its color. If you dig a hole at least 1 m deep, you will get a soil profile, that is, the structure of the soil in cross-section. On the side wall of the pit, one can successively trace the alternation of soil layers and the change in their color towards the bottom of the pit. The color of the soil is directly related to such characteristics as the level of fertility.

This is a completely logical conclusion, since the appearance of the soil and its fertility are determined by numerous factors that influenced its formation. Dark soils, as a rule, are characterized by more high level fertility, as they represent Better conditions for the growth of plants and the activity of soil microorganisms than light soils. The color of dark soils is due to the increased content of soil soil in them. organic matter humus. It is humus good quality contained in the soil in sufficient quantity, determines the rich dark color of the soil. However, not only humus provides one or another color of the soil, but also numerous chemical compounds, for example, iron oxides, which give the soil brown, reddish, reddish-rusty and yellowish shades. Plates of a bluish-gray or gray color may appear on the soil profile at different depths, which is a bad characteristic of the soil of the site, as it indicates the presence of constant waterlogging of the soil, which results in the formation of ferrous compounds. Such soil will require great efforts to improve, but a lot also depends on
depths of blue clay strata.

In addition to special analysis, there are a number of methods for conducting soil analysis yourself.

Of course, such methods will not produce a chemically accurate assessment of all the characteristics of the soil in a particular area, but they will give you an idea of ​​its main parameters and allow you to make correct solution on further processing and fertilization of the soil. A home mini-laboratory will help with this, which is a set of reagents and indicators, equipped with a color scale for comparative analysis acid-base reaction of the soil using indicator paper and detailed description all possible soil tests. In addition, the soil can be examined visually. This will give you at least a fairly good idea of ​​the structure and composition of the soil.

If you make a hole one or two shovels deep and examine the profile of the cut, then by the color of successive layers you can approximately determine what kind of soil you are dealing with. Most often, the top layer is darker than the subsequent ones, which indicates a higher content in it. organic matter or humus. Its thickness may vary, but it is advisable that it should not be less than 1015 cm, that is, the depth where plant rooting occurs. Peat soils are almost black in color due to great content they contain organic matter. The sandy layer of the earth has a yellowish
gray color, loamy layer - light brown with various shades, clay layer can be different colors- from brown and reddish to whitish.

Manual soil testing

If you are not entirely sure what the composition of the soil in your area is, you can check it in the following way: take a handful of damp, but not wet, soil and rub it between your fingers. If the soil texture is granular, if it does not stick together or roll into balls, you have sandy loam or sandy soil.

If the soil is grainy but rolls into a ball or clump, it is sandy loam.

If the soil has a grainy or sticky texture and you can roll it into a sausage between your palms, then you are dealing with oily sandy loam.

If the resulting sausage is flexible, it can be bent into a ring and it will not break, it is clay.

Knowing the structural properties of your soil can help you determine what steps you need to take to improve it.

When examining the soil manually, it is not difficult to see that individual soil particles are completely different from each other. In sandy soils or soils with a high sand content, solid particles are large and coarse and can be clearly felt to the touch. The more the soil sticks together, the smaller and thinner its particles are, which indicates a high clay content in the soil. Good soil has a mixed composition of coarse and fine particles, which form into small loose lumps. Soil with a high humus content has a pleasant, healthy smell of forest soil, rotten leaves and grass.

Time to take a soil sample

The accuracy of the analysis also depends on time. A soil sample should be taken in early spring or late autumn, that is, before or after the growing season of plants. If the sample is taken in the spring, this must be done before applying fertilizers; if in the fall, then after at least 2 months have passed after the last application of fertilizers and before they are applied for autumn digging.