Soil probe or shovel; however, backhoe, soil auger or posthole digger may be used.
Clean moisture-proof quart-size bags. Use paper bags only if soil is very dry.
Clean plastic bucket to mix samples, optional.
Samples collected for microbiology, nematode and pesticide residue analysis generally need refrigeration so have a cooler and coolant available.
Procedure:
Walk a zigzag course around or through the sampling area taking 20 to 30 cores, enough to make a quart of soil. Stay away from field edges.
For furrow or field crops, take soil 12 inches below the surface or to the plowing depth.
For tree and vine crops, soil samples should be taken one-foot increments to the depth of rooting which may require three to five samples from the same area.
Collect one quart of soil and put in a clean quart-size bag.
If collecting soils from multiple sites, composite by mixing in clean plastic bucket and taking one quart per sample.
Clearly print on each bag using an indelible marker or ballpoint pen your name/company, site and sample description.
Complete Work Request form. Print clearly and return it with your sample.