Sulfur: just enough is the trick
19 April 2022
Sulfur (S) is an important nutrient for both grass and cows. Too little leads to deficiencies and yield losses. Too much leads to cows not being able to absorb enough trace elements. Accurate fertilization is therefore the trick. Soil Check and Freshgrass Check help with this. Just like the S-index on the report of forage value research.
In the soil, sulfur is largely sequestered in the organic matter. A relatively small part is in the soil moisture. Therefore, grass can only absorb a small amount of sulfur from the soil.
Especially in spring, the supply of sulfur from the soil is limited. In the past, this was not a problem because there was sufficient sulfur from the air to the soil. However, the air has become cleaner and the amount of sulfur from the air (deposition) has thus become smaller.
For the first, and partly also for the second, cut it is important to keep a close eye on sulfur. Soil Check in the spring indicates how much mineral sulfur is available for the crop. It is also possible to check how much sulfur has already been taken up by the grass via Freshgrass Check.
Sulfur, methionine and trace elements
One of the important functions of sulfur in grass is the production of amino acids. Amino acids such as methionine cannot be produced by the cow itself and it is therefore dependent on the supply from the feed. Sulfur is a building block of the essential amino acid methionine, so the importance of sulfur is great.
In addition to a shortage, an excess of sulfur can also be fertilized and absorbed. Annually, grass absorbs a maximum of 50 kg of sulfur. If the fertilization of sulfur on grassland is too high, a negative effect of sulfur on the uptake of trace elements can be expected. And trace elements are also important for the health of the cow.
It is therefore important to start fertilizing precisely. In addition to Soil Check and Freshgrass Check, the forage value survey of recent years is also an important tool. The report shows what was taken from the land last year and provides relevant information about the utilization of sulphur, among other things. The report also includes the S-index, which can be used to improve the efficient use of sulfur.
Watch the video below about the S-index: