To keep agricultural production in harmony with the environment, Nitrate Vulnerable Zones (NVZ's) are being established in many areas of the UK. It is likely that the legislation will increase the need for strict adherence to sustainable production techniques.

Click here for our soil analysis and sampling pricing guide

Click here to apply for a soil sampling analysis

In NVZ's it is a requirement to follow the codes of practice for air, soil and water, operating in accordance with bulletin RB209, when applying fertilizer to arable crops. RB209 recommends soil sampling to 90 cms with analysis (the SMS analysis method) where high or uncertain amounts of soil nitrogen can be expected.

It states 'Direct measurement and estimation of the key components of SNS (SMN, total crop N and mineralisable N) will usually result in the most accurate assessment of the amount of soil nitrogen available for the crop, and therefore the most accurate nitrogen fertilizer decision.'

Envirofield operate Geonor deep sampling equipment mounted on a six wheel ATV and can sample fields quickly and representatively to give an accurate measure of SMN, usually the largest contribution to Soil N Supply.

The next largest contribution for Autumn sown crops will be the N that has been taken up over Autumn and Winter. Envirofield estimate this amount using a large amount of research data collected to relate crop appearance in spring and the amount of N already taken up.

The smallest contribution will be from soil organic N that mineralises in late Spring/early Summer. Where the organic matter content of the soil is low to average, it is suggested in RB209 that this amount of N can be ignored. For higher organic matter soils, Envirofield use a typical value derived from trial work.

From this data Envirofield will produce a SNS index which relates directly to the tables in bulletin RB209 and from which exact crop nitrogen requirements can be calculated.
Results Summary Kg N/ha
Measured soil min N 67.4
Estimated N in Crop 25
Soil mineralisation 5.0
Total Soil N Supply 97.4
Total Soil N SupplyIndex (SNS) 2
Lab Ref Field Depth NH4 N
dry soil
mg/kg 		 NO3 N
dry soil
mg/kg 		 Estimated
Available N
kg/ha 		 Estimated
Available N
(0 - 90)  kg/ha
020564 Riverside 0 - 30 0.1 8.7 31.8  
020565   30 - 90 <0.1 4.2 35.5 67.4

~

For more information on our Soil Sampling Service,

Please click Contact Us