The history of the use of UAN in Russia has been going on for several decades. And the percentage of consumption of this convenient fertilizer, which is easy to use, is growing steadily today. Currently, UAN is the most common type of nitrogen fertilizer in Russia and the countries of the former CIS.
Structure
What is CAS and with what ingredients is it made? This tool is a liquid mineral fertilizer, which includes:
The composition of KAS fertilizer includes 27-32% of nitrogen from the total mass. This component is presented in top dressing in three main forms:
Nitrate nitrogen is absorbed by the roots of plants immediately after it enters the soil. The ammonium form until this moment undergoes insignificant, short-time transformations. Amide nitrogen is the most difficult to digest variety. After being introduced into the ground, this substance first passes into the ammonoid, and then into the nitrate form.
Benefits of using
So, what is CAS, we found out. But what are the advantages of using it? What explains such a huge popularity of this fertilizer among agricultural workers? First of all, the benefits of UAN plant growers include the convenience of its storage, transportation and use.
Unlike the same widely used ammonium nitrate, the urea-ammonia mixture is explosive. Therefore, for its storage, you do not need to make additional costs for the purchase of special warehouse equipment and the creation of any special conditions in the premises themselves. Transporting CAS is also very simple.
Since UAN has a liquid form, it is distributed in the soil as evenly as possible. Enough of such a remedy after application to all plants planted on the field.
The use of UAN fertilizer, among other things, is convenient because, unlike ammonium nitrate, when applying this fertilizing to the ground, it is not necessary to use any complex technologies. Loss of nitrogen when using this tool almost never happens (about 10%). With the soil complex, in contrast to granular compositions, it binds very tightly.
Foliar top dressing
Unlike conventional urea, CAS contains a small amount of biuret. Therefore, it is very convenient to use including for foliar top dressing. Among the undoubted advantages of UAN liquid fertilizers, among other things, they also include the fact that they have practically no toxic effect on plants. Due to the low biuret content, it became possible to introduce more nitrogen into the composition of this agent. And consequently, the effect of using such fertilizer is always pronounced.
What are the disadvantages
The main disadvantage of this fertilizer, agricultural workers consider the need for exact adherence to dosages. If CAS on the field is introduced in too low concentrations, it will not have a special positive effect on plant development. Exceeding doses when using this fertilizer often leads to burns on the green parts of crops and their roots.
Varieties
What is CAS is thus understandable. Currently, 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 buy CAS 28, 30 and 32%. CAS with a nitrogen concentration of 32% is more expensive than the first two forms. But at the same time, such a variety is considered the most effective and is most often used for plant nutrition.
To introduce this drug into the soil is more convenient than granular formulations. However, a special type of special equipment is still necessary for farms using CAS.
When and how to make in the fields
Instructions for the use of UAN fertilizer in the cultivation, for example, of grain, are quite simple. Crops are fed with this fertilizer usually three times per season. For the first time, this is done immediately after the snow has melted and the vegetation has recovered. During this period, UAN is used in such an amount that 30-60 kg of nitrogen per 1 ha.
For the second time, CAS is introduced in fields with cereal plants during the period of recruitment of green mass plants. This time, special tubular equipment is used for feeding. CAS is introduced into the basal zone, restricting exposure to the upper green parts.
The third and fourth top dressing using this fertilizer is carried out at the stage of milk maturity of cereals. This time, the product is sprayed on the sheet. The fertilizer itself is diluted with water in a ratio of 1: 2.5 before performing this procedure.
Mixes
Often in farms CAS is used in combination with other fertilizers. This takes into account the fact that:
mixed with foundationol CAS is used in spring on winter crops;
with retardants - at the beginning of trumpeting;
with fundozole and retardants - in the middle of trumpeting.
Weather effect
It is believed that the maximum effect from the use of UAN can be achieved if the active substance will cover the green parts for as long as possible. This can be achieved in non-hot and cloudy weather. The optimal air temperature for the use of CAS is considered to be 20 ° C. Under these conditions, plants receive the maximum amount of nitrogen during feeding and do not burn on them.
The air outside when using this fertilizer should also be sufficiently humid. If it is too dry, the plants may be damaged. The minimum humidity indicator when using CAS is 56%.
Use in gardens: instructions for fertilizing CAS
In suburban areas, UAN can also be used for both root and vegetative top dressing. In the first case, this fertilizer is simply poured on the surface of the soil with a uniform layer. In the heat after performing this procedure, the wetted layer is lightly dug up with earth. Spraying the plants with the product is done in the morning or in the evening.
There should be no dew or raindrops on the green parts of crops when using this top dressing. Wet plant leaves become very sensitive. At the same time, the upper layer of green tissues begins to pass the solution very quickly inside. And this, in turn, can greatly harm plants.
Day and night to use this fertilizer for feeding garden crops is highly not recommended. In hot weather, the droplets left on the leaves will act like small lenses. This will result in 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, nitrogen absorption by plants is significantly slowed down. Accordingly, the product remains on the green parts and comes into contact with them for a long time, which leads to burns.
Country equipment
Spill the soil under plants using CAS mineral fertilizer from ordinary watering cans. For spraying, it is worth using, of course, a spray. You can buy for CAS any equipment of this type. Spray fertilizer should be in calm weather, wearing gloves and glasses.
What machines are used in large farms
When applied to fields under CAS, standard equipment is also used. The only thing in this case, with sprayers and cultivators, all parts of non-ferrous metals are changed to plastic or steel. Otherwise, the equipment will subsequently fail.
To conduct the first foliar top dressing, farms use not slotted nozzles, but deflector ones. 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 CAS solution first moisten the leaf, and then roll down to the ground - to the roots.
The following vegetative top dressing is done already using slot nozzles. This allows you to process the bushes completely. In any case, in equipment designed to introduce CAS, the nozzles must have an adjustment of rotation.
For fertilizing under the root of plants, among other things, special extension hoses with weighting agents can also be used on farms. Such equipment allows you to effectively fertilize crops and at the same time avoid the appearance of burns on their green parts.
It is allowed to introduce UAN in the fields when using agricultural equipment both in concentrated form and in diluted 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
The use of UAN nitrogen fertilizer in the fields can actually be cost-effective. According to studies, the use of this mineral product allows you to:
increase wheat productivity from 35-38 kg / ha to 45-50 kg / ha;
to improve the quality of grains 4-5 grade to 2-3;
increase potato productivity by 5 t / ha.
How to store
With what CAS and how to use it, we figured out. Next, we determine how to properly transport and store such fertilizer. Transporting and storage of CAS, as already mentioned, is quite convenient. The economic benefit of using this fertilizer for operating costs, according to statistics, is 9% for each ton of nitrogen.
CAS solutions are not explosive and have an alkaline reaction. However, it is still not recommended to transport and store them in metal containers or intended for water. Such barrels and cans under the influence of this top dressing, unfortunately, are destroyed after only 2-3 years. Use for storage of UAN, therefore, it is recommended that special plastic containers designed for ammonia water. Special soft elastomer canisters can also be used for this purpose.