What is CAS: fertilizer composition, types, release form, purpose and instructions for use

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

The history of the use of CAS in Russia goes back several decades. And the percentage of consumption of this easy-to-use effective fertilizer is steadily increasing today. Currently, UAN is the most common type of nitrogen fertilizer in Russia and the former CIS countries.

Composition

What is UAN and what ingredients are used to make it? This tool is a liquid mineral fertilizer, which includes:

• carbamide - 30%;
• ammonium nitrate - 40%;
• water and corrosion inhibitors - 30%.

The UAN fertilizer contains 27-32% nitrogen of the total mass. This component is presented in top dressing in three main forms:

• ammonium;
• nitrate;
• amide.

Nitrate nitrogen is absorbed by plant roots as soon as it enters the soil. Ammonium form up to this pointundergoes minor, short-term transformations. Amide nitrogen is the most indigestible variety. After being introduced into the ground, this substance first passes into the ammonide and then into the nitrate form.

Benefits of using

So, what is CAS, we found out. But what are the benefits of using it? What explains such a huge popularity of this fertilizer among agricultural workers? First of all, the advantages of UAN plant growers include the convenience of its storage, transportation and use.

Unlike the same widely used ammonium nitrate, carbamide-ammonia mixture is an explosion-proof substance. Therefore, for its storage, it is not necessary to make additional costs for the purchase of special storage equipment and the creation of any special conditions in the premises themselves. It is also very easy to transport CAS.

Since UAN has a liquid form, it is distributed in the soil as evenly as possible. Enough of such a tool after making all the plants planted on the field.

The use of UAN fertilizer, among other things, is convenient because, unlike ammonium nitrate, when applying this top dressing to the ground, it is not required to use any complex technologies. Nitrogen losses almost never occur when using this agent (about 10%). With a soil complex, unlike granular compositions, it binds very tightly.

Foliar applications

Unlike conventional urea, UAN contains a small amount of biuret. Therefore, it is very convenient to useincluding for foliar dressings. The undoubted advantages of UAN liquid fertilizers, among other things, include the fact that they have practically no toxic effect on plants. Due to the reduced content of biuret, it became possible to introduce more nitrogen into the composition of this product. And consequently, the effect of using such a fertilizer is always pronounced.

What are the disadvantages

The main disadvantage of this fertilizer, agricultural workers consider the need for precise dosages. If CAS is applied to the field in too low concentrations, it will not have a special positive effect on the development of plants. Exceeding the doses when using this fertilizer often leads to burns on the green parts of crops and their roots.

Varieties

What is CAS is thus clear. At the moment, there are a total of three brands of such fertilizer on the market. They differ not in composition, but in the mass fraction of nitrogen. If desired, today you can purchase UAN 28, 30 and 32%. UAN with a nitrogen concentration of 32% is more expensive than the first two forms. But at the same time, this variety is considered the most effective and is used to feed plants most often.

It is more convenient to apply this preparation to the soil than granular formulations. However, farms using UAN still have to purchase a special type of special equipment.

When and how to bring in the fields

The instructions for using UAN fertilizer when growing, for example, cereals, are quite simple. Feed crops with this fertilizer usually three times per season. For the first time, this is done immediately after the snow melts and the vegetation is restored. During this period, UAN is used in such quantity that 30-60 kg of nitrogen per 1 ha.

For the second time, UAN is applied in the fields with cereals during the period when the plants are gaining green mass. This time, special tubular equipment is used for feeding. Apply CAS to the root zone, limiting the impact on the upper green parts.

The third and fourth top dressing using this fertilizer is produced at the stage of milk maturity of cereals. This time, the product is sprayed onto the sheet. The fertilizer itself, before performing this procedure, is diluted with water in a ratio of 1: 2, 5.

Mixes

Often on farms UAN is used in combination with other fertilizers. At the same time, take into account the fact that:

• mixed with foundationazole UAN is used in spring for winter crops;
• with retardants - at the beginning of blowing;
• with fundozol and retardants - in the middle of the pipe.

Influence of weather

It is believed that the maximum effect from the use of CAS can be achieved if the active substance covers the green parts for as long as possible. This can be achieved in cool and cloudy weather. The optimum air temperature for the use of UAN is considered to be 20 °C. Under such conditions, the plants receive the maximum amount of nitrogen when fertilizing, and at the same time, burns do not appear on them.

Outdoor air atusing this fertilizer should also be sufficiently moist. If it is too dry, the plants may be damaged. The minimum humidity indicator when using CAS is 56%.

Use in vegetable gardens: instructions for UAN fertilizer

In summer cottages, UAN can also be used for both root and vegetative dressings. In the first case, this fertilizer is simply poured over the soil surface in an even layer. In the heat, after performing this procedure, the wetted layer is slightly sprinkled with earth. Spraying plants with a remedy is done in the morning or in the evening.

Dew or raindrops on the green parts of crops when using this top dressing should not be in any case. Wet plant leaves become very sensitive. At the same time, the top layer of green tissues begins to let the solution inside very quickly. And this, in turn, can greatly harm the plants.

Day and night use of this fertilizer for feeding garden crops is highly discouraged. In hot weather, the droplets left on the leaves will act as small lenses. This will cause burns on the green parts of the plants. The same danger of damaging crops, oddly enough, exists with night spraying. At this time of day, the absorption of nitrogen by plants slows down significantly. Accordingly, the agent remains on the green parts and contacts with them for a long time, which leads to burns.

Country equipment

Spill the soil under the plants withthe use of mineral fertilizer UAN is possible from ordinary watering cans. For spraying, it is worth using, of course, a sprayer. You can buy any equipment of this type for CAS. Fertilizer should be sprayed in calm weather, wearing gloves and goggles.

Which machines are used on large farms

When making fields under CAS, standard equipment is also used. The only thing, in this case, for sprayers and cultivators, all parts made of non-ferrous metals are changed to plastic or steel. Otherwise, the equipment will quickly fail in the future.

For the first foliar top dressing on farms, not slotted nozzles are used, but deflector nozzles. With the use of such tools, it is possible to perform large-drop spraying. And this, in turn, improves the efficiency of fertilizer use. Large drops of UAN solution first wet the leaf and then roll down to the ground - to the roots.

The next vegetative top dressing is already done using slot nozzles. This allows you to process the bushes completely. In any case, in equipment intended for the application of UAN, the nozzles must have a rotation adjustment.

To apply fertilizer under the root of plants, among other things, special extension hoses with weights can be used on farms. Such equipment allows you to effectively fertilize crops and at the same time avoid burns on their green parts.

Apply CAS in the fields when usingagricultural equipment is allowed both in concentrated form and diluted with water (preheated). The advantages of this fertilizer, among other things, include the fact that it absolutely does not pollute the environment.

How justified is the application

Using UAN nitrogen fertilizer in the fields can actually be cost effective. According to studies, the use of this mineral remedy allows you to:

• increase wheat yield from 35-38 c/ha to 45-50 c/ha;
• improve the quality of grain 4-5 class to 2-3;
• increase potato yield by 5 t/ha.

How to store

We figured out what CAS is and how to use it. Next, we will determine how to properly transport and store such fertilizer. Transporting and storing UAN, as already mentioned, is quite convenient. The economic benefit from the use of this fertilizer in terms of operating costs, according to statistics, is 9% for each ton of nitrogen.

UAN solutions are not explosive and have an alkaline reaction. However, it is still not recommended to transport and store them in metal containers or those intended for water. Such barrels and canisters under the influence of this dressing, unfortunately, are destroyed after 2-3 years. Use for storage of UAN, therefore, it is recommended to use special plastic containers designed for ammonia water. You can also use special soft canisters made ofelastomer.