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Materials required:

• Paper to draw a map

• An apple corer or pipe that is about 0.5 to 1.5" interior diameter

• One resealable plastic bag per sample to be analyzed

• Permanent marker to label bags

• Sterilized plastic bucket

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1. Draw a map of the area to be sampled and overlay a grid with 1 square per acre. Assign each square a number.

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2. Use a random number generator and come up with 10 numbers (from 1 to however many number of acres on your grid map). These will correspond with areas on the grid where soil cores are to be collected for the sample. If you get more than 2 numbers that line up in a row on the grid, keep generating random numbers until you do not.

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3. Within each square go to 5 spots; each corner and the center (ok if not exact). Avoid going right to the boundary of the field and to any areas that are not representative of the field e.g. the ridge line or a depression. Collect a soil core at each of these 5 spots within the square. To take a soil core, move aside the top layer of dead or living plant material if present and then collect only the top 3 inches of the soil with your apple corer or pipe. Place these 5 soil cores into the bucket. 

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4. Repeat step 3 for the next 4 squares so that by the end of sample collection you have a total of 150 soil cores in a bucket.

 

5. Very gently mix up the soil cores so that a smaller sample taken from the bucket is representative of the whole area to be assessed.

 

6. Fill a plastic bag 1/3 to 1/2 of the way full and then seal the bag. It is very important not expel the air from the bag as this will limit the oxygen available to the biology in the sample which may result in anaerobic conditions being formed.

 

7. All sample bags should be labeled with the name, area, date, and time collected on the *outside* using a

permanent marker or an affixed label. Please do not put any identifying information about your

sample on a piece of paper and place it inside the bag. The paper will disintegrate, become food

for microbes, and potentially change the biology of your sample.