1. Begin sampling at the Start Point indicated on the sampling plan. There may be from 1 to 12 start points in each field.
2. Collect one small scoop (3 to 5g) of surface soil from the top 2 cm of soil from each of 4 spots at the initial sampling location.
3. Walk 4 paces away from the corner diagonally towards the opposite corner. If diagonal pacing is difficult, walk 4 paces along the crop row and 2 paces across rows to the next sampling location and repeat step 2 (i.e. Collect one small scoop of surface soil from the top 2 cm of soil from each of 4 spots).
4. Repeat steps 4 and 5 until small cotton bag (soil sample bag 3 1/2" x 5", Hubco) is full (8 to 10 sampling locations across 30 to 40 meters should be sampled for each Start Point on the sampling plan). Total sample weight is only 100 to 175g so each scoop is 3 to 5 grams each.
5. Sampling should be adjusted for the site. Some fields may be less than 40 meters across. In such locations, the sub samples should be taken from across the entire field in a manner that best represents the location.
- Sample Only Dry Soils. If slightly moist samples must be taken, they must be placed in a forced-air drying oven at 40 C as soon as possible after sampling.
- Soils need to be kept seperate. After sampling and the cotton bag is filled with dry soil, it should be placed in an individual ziplock bag (quart size) and sealed. If condensation forms on the bag at any point, that sample must be dried in the forced air oven at 40 C for 24 to 48 hr.
- Make sure bags are properly labeled. Every bag label must have the field indicated. If possible, GPS reading should be taken at the start point.
- Do not allow the samples to bake in the sun. Please keep soil samples shaded and cool as possible at all times. If possible, keep in air-conditioned space until shipped.
- If the soil in the field is hardened. You may need a hammer to break up the surface soil prior to sampling.
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