Here is some informaiton which can affect results obtained from soil testing.
"Factors Effecting Irregularities in Soil Analysis"
"Factors Effecting Irregularities in Soil Analysis"
1. Varied depth of sampling (Sample at tillage depth).
2. Combining unlike soil areas into one composite sample.
3. Combining soil areas with different past liming, fertilizer, or cropping histories into one composite sample.
4. Combining an insufficient number of sub-samples into composite from extremely varied or land-leveled fields.
5. Attempting to use singgle composite sample for too large an acre.
6. Varying amounts of organic matter or undercomposed organic matter in sample.
7. Soft rocks in sample.
8. Forded drying of soil sample at high heat.
9. Soils that have been sampled, dried, or processed in contaminated containers.
10. Improper packaging of samples, allowing contaminants to become part of sample.
11. Mixing sample identity.
12. Improper sampling equipment (Do not use galvanized or cadmium based equipment. Do not lubricate with other than food oil).
13. Poor distribution of manure applications.
2. Combining unlike soil areas into one composite sample.
3. Combining soil areas with different past liming, fertilizer, or cropping histories into one composite sample.
4. Combining an insufficient number of sub-samples into composite from extremely varied or land-leveled fields.
5. Attempting to use singgle composite sample for too large an acre.
6. Varying amounts of organic matter or undercomposed organic matter in sample.
7. Soft rocks in sample.
8. Forded drying of soil sample at high heat.
9. Soils that have been sampled, dried, or processed in contaminated containers.
10. Improper packaging of samples, allowing contaminants to become part of sample.
11. Mixing sample identity.
12. Improper sampling equipment (Do not use galvanized or cadmium based equipment. Do not lubricate with other than food oil).
13. Poor distribution of manure applications.
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