LaMotte Soil Chemistry Test Equipment - Manual (Page 5)

SOIL SAMPLING
Representative soil sampling is the first step in successful soil fertility
management. Accurate interpretation of soil test results largely depends
on the care and organization applied to the sampling process.
Get to know your garden. Supplement soil tests with careful observation of
the effects of shade, moisture, temperature, weeds, insects, and other
conditions influencing plant development.
Establish sampling areas. Different plants prefer different soil conditions.
Your garden may contain several soil types. Divide your garden into
distinct sampling areas, so that test results may be interpreted in terms of
the soil type and the plants to be grown in a specific area.
Take composite samples. Within a particular sampling area, collect and
thoroughly mix at least five random samples. The resulting composite
sample insures that test results will be representative of the entire sampling
area. Do not mix samples from separate sampling areas.
Sample the root zone. Collect samples directly where plants are to be
grown and to a depth compatible with root development. The root zone is
where the transfer of nutrients from soil to plant occurs. Samples should be
taken 2-3 inches below the soil surface for garden crops.
Make sure samples are free of foreign objects. Scrape away ground cover
before sampling. Avoid contamination with fertilizers and sprays. Minimize
contact with hands. Use a clean trowel, spoon, knife or soil sampling tube
to collect samples. A sampling tube permits inspection of core samples
and accurate measurement of sampling depth. Collect the composite
sample for a given area in a clean plastic bag, paper cup, or other
suitable container. Label the container to identify the sampling area.
Keep a soil-plant diary. Periodic testing and accurate recordkeeping
provide the only means of correlating test results, fertilizer applications,
and plant growth. Record the specific areas from which soil samples were
taken. Use the form at the back of the manual or devise your own.
SOIL PREPARATION
1.
Spread out the composite sample on a clean sheet of paper or plastic.
2. Allow the soil to dry several hours or overnight. Do not bake the
samples to accelerate drying.
3. Remove foreign matter such as leaves, twigs and stones.
4. Gently crush soil to remove lumps.
5. Sift the sample through a screen or flour sifter to give a uniform sample.
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