Standard | GPS | pH | Broad Spectrum
Soil analysis data is only as good as the sample taken. A sample normally comprises around 1kg of soil which is taken to represent an entire area or field., which contains around 2,000 tonnes of soil per hectare to a plough depth of 20cm (8 inches). It is therefore imperative to otain as representative a sample as possible or the results will not reflect the nutrient status accurately.
We at JSE-Systems take at least 25 cores from each area to be sampled, or where GPS soil sampling and mapping is to be carred out an average of 16 soil cores are taken form each hectare square. The cores are then put together to form a single representative sample. Theses are then thoroughly mixed together and a sub-sample is taken from this and dispatched to the laboratory.
Normal depth is 15cm for arable crops (upto 30cm in min till) and 7.5cm for grassland.
The effects of different cultivations systems on sample techniques
Standard and GPS Soil Mapping
What is measured
pH Soil Sampling
Broad Spectrum Analysis
Variations in analysis between laboratories
Soil P, K & Mg concentration (mg/I) and Defra Index Scale
Note that the Index is split in half for potassium only and described as 2- (or lower Index 2) and 2+ (or upper Index 2). In the past, Index 2 was not divided in half for potassium but some soil reports used positive and negative signs to denote the extreme top and bottom 10% of each band.