Nitrate (NO₃⁻)
Definition
Nitrate (NO₃⁻) is the primary form of nitrogen absorbed by crops. It is highly soluble and quickly taken up by plants, making it an essential nutrient for growth.
Importance
Nitrate plays a key role in crop nutrition and soil health. Fertilising with nitrate or ammonium not only boosts plant growth but also stimulates soil life, accelerating the breakdown of organic matter.
Behaviour in soil
While nitrate is beneficial, it is prone to leaching during wet conditions and can volatilise in very wet weather. This makes timing and application critical for efficiency and environmental protection.
Measurement and indicators
Nitrate levels are easy to determine and serve as a measure of fertiliser effectiveness. However, improper fertilisation—such as applying nitrogen too close to mowing—can lead to high nitrate fractions in silage.
Impact on silage and livestock
Excess nitrate in silage reduces palatability and can pose health risks to cows. High nitrate fractions often indicate poor timing of fertilisation and require careful management to maintain forage quality.
