Covering the soil with straw helps to retain moisture, which is beneficial in dry conditions. Straw protects the soil from wind and water erosion. Decomposing straw adds organic matter to the soil, improving its structure. Introducing straw into the soil enhances its water retention ability. Straw in the soil undergoes various processes. Through biological decomposition, soil microorganisms break down straw, transforming it into simpler chemical compounds and humus. During mineralization, the nutrients contained in the straw are released in a form available to plants. Straw is rich in carbon but poor in nitrogen. Its decomposition in the soil requires additional nitrogen, which can lead to temporary nutrient starvation in plants. Adding straw to the soil improves its structure, contributing to the formation of stable soil aggregates.

Straw as fertilizer
As noted, straw is rich in carbon but low in nitrogen. When incorporated into the soil as a fertilizer, microorganisms in the soil break it down, requiring nitrogen in the process. This is why farmers often add additional nitrogen when mixing straw into the soil to ensure a C:N (carbon:nitrogen) balance. Straw decomposition in the soil leads to the formation of humus, which benefits soil structure and plant health. It is important to evenly distribute straw in the field. Uneven distribution can lead to irregular organic matter distribution in the soil and inconsistent nutrient access for plants. To improve distribution in the field, the Rolmako SpringExpert mulch harrow can be utilized.

Straw serves as a valuable fertilizer and should be utilized in the field or substituted with manure, an even superior alternative. Combining straw with manure is a strategy employed in numerous agricultural systems to maximize the advantages of both materials.

The estimated grain-to-straw yield ratios are as follows:
- wheat: 1:0.8,
- barley: 1:1,
- rye and triticale: 1:1.2–1.4.

For instance, if wheat yields 10 tons of grain per hectare, it would leave approximately 8 tons of straw in the field.
Proper utilization of crop residues can yield substantial savings, a critical consideration given the increasing fertilizer prices. For example, maize contributes up to 15 tons of dry matter of such residues per hectare, which are rich in essential nutrients such as nitrogen, phosphorus, and potassium. These residues serve as a valuable source of organic matter, store nutrients, and enhance soil quality.

Content of individual components in straw
Upon closer examination of the individual components in straw from various plant species, it is evident that it serves as a valuable fertilizer. It contains both macro and micronutrients in significant quantities. However, it has relatively low phosphorus content, as this element is mostly removed with the grain yield due to its presence in protein.

Straw is challenging to manage due to its wide carbon to nitrogen ratio of 50-80:1, compared to manure which has a C:N ratio of 15-20:1. In soils with higher mineral nitrogen content, straw mineralizes more quickly. The microorganisms responsible for this process require nitrogen to multiply and decompose the carbon in the straw. If nitrogen is insufficient, it should be supplemented in small quantities. In terms of mineral fertilizer, this equates to approximately 20-30 kg of pure nitrogen per hectare. It is important not to exceed these doses, as high levels, particularly in wet years, can lead to fermentation rather than mineralization of the straw, resulting in the accumulation of soil-acidifying substances like hydrogen sulfide, methane, and acids such as acetic and butyric acids. An effective method involves first mixing the straw with the soil, then applying manure or slurry, and quickly mixing the fertilizers again to prevent nitrogen loss from natural fertilizers. A highly effective alternative for accelerating straw decomposition is using lime instead of nitrogen at a dose of 1.5 t CaO per hectare. This approach helps maintain soil pH, which supports mineralization and reduces straw rotting. Furthermore, straw, especially corn straw, should be crushed for faster decomposition, using equipment such as a Rolmako ProCut or TurboCut knife roller. This method also helps limit corn borer infestations on the plantation.

Mixing straw with soil
To accelerate the decomposition of straw, it is advisable to incorporate it into the soil to a depth of several centimeters using disc harrows or cultivators. Mixing straw with soil is a crucial land management practice. This incorporation prevents straw from being blown away by the wind or transported by water. For deeper mixing, ploughs can be utilized, though this method is more invasive and may disrupt soil structure. Cultivators can incorporate straw into the soil to a depth of several centimeters. Rolmako offers a range of aggregates for this purpose. Disc harrows disperse and mix straw into the soil's surface layers. The optimal approach for straw management is ultra-shallow cultivation with a cultivator or disc harrow, such as Rolmako's ComboTill aggregate or the SpeedCutter harrow. Ultra-shallow cultivation involves lightly incorporating straw into the topsoil. Leaving substantial plant residue on the soil surface protects against water and wind erosion. Straw and other plant residues act as mulch, reducing water evaporation. This practice also promotes soil microorganism activity, contributing to healthier soil. For deeper straw mixing, Rolmako provides the U436 three-beam no-plough cultivator. Typically, straw is incorporated immediately after harvest, though it may be left on the surface in some farming systems to protect the soil over winter.

Straw as erosion control
The undeniable advantage of straw left in the field is that it limits erosion in a no-till system. Well mixed with the soil (but not left on its surface), it stabilizes it and reduces susceptibility to washing out (limiting surface runoff) or the negative effects of strong winds. These always blow away the most valuable soil particles, i.e., dust and clay. Conversely, straw also causes the earth to heat up longer, especially in heavier sites, and promotes the accumulation of pathogenic fungi and is a suitable place for pests to overwinter and develop. Unfortunately, it also favors weeds because their seedlings can be covered by straw in the initial stages, limiting the access of herbicides. This must be accounted for when protecting plants. Straw, if properly managed, can bring benefits to the land and agricultural production, but it is important to use it properly and consider the specifics of local soil conditions. Proper straw management in agriculture allows for maximizing the benefits from its use while minimizing potential negative effects on the soil and crops.

Terminology
Humus - enhances the water retention and absorption capacity of the soil.
Soil aggregates - clumps of various shapes and sizes with different durability that have formed in the soil due to the binding of individual mineral grains. They constitute the structure of the soil.