The first thing to consider when looking at the finer details of grassland management is whether you have a full understanding of good soil structure and its nutritional status. If the answer is no, then to get the maximum benefit from a reseed or established leys, I would always advise checking the soil structure and sampling on a field-by-field basis. This will help to determine important factors such as the pH of your soil which is essential for nutrient availability, as well as the current levels of N, P, K and other elements.
Why is soil structure so important?
Grass breeder, Germinal, recently identified that soil which is moderately damaged – with poor soil structure and which is suffering from compaction issues can reduce yield by up to 30% and significantly increase the risk of weed ingression. This can have a significant impact on on-farm margins as you may have to supplement the losses with bought-in feed. A compacted soil structure can increase machinery fuel costs by 50%+ and poor drainage can lead to flooding, soil erosion and water pollution.
Signs to look out more in damaged soils
The condition of the soil structure can be identified in several ways. Below are all key indicators of soil health and structure. Digging a hole can be the best way to assess for potential problems. This soil sample will be ideal for assessing the soil profile and identifying any issues.
- Colour
- Smell
- Horizontal cracking
- Amount of Worm activity
- Rooting issues
- Soil organic matter breakdown
For advice on checking your soil’s structure for grassland, click here to find a scoring system which will help you determine if your soil is experiencing any issues.
How to improve soil structure using fertiliser
Blanket fertiliser applications across all grassland field types can lead to overspending or more likely inaccurate spending – where the grass crop does not get the full benefit of the application. The most common example of this is when the soil pH is below the recommended levels.
For peaty soils, the range is 5.0 to 5.5 and for mineral-based soils, it is 6.0 to 6.5. If you have not tested the pH of your soil, and the levels fall outside these, it will often hamper the nutrient availability to your grass crop. This means that fertiliser that has been applied could go unused and is wasted – and so is the financial investment. For example, if your soil pH is between 5 and 5.5, up to half of your nitrogen can be lost rather than used by the grass crop. Consequently, producers could be wasting half of their N expenditure simply because they did not apply lime prior to reseeding.
For more information on soil analysis and bespoke grassland fertiliser plans, speak to your local specialist or Wynnstay’s Fertiliser Department on 01939 211266.
