MAP AREAS for a permanent numbering system. Make one composite sample that is representative of a uniform area for each unit sampled. For high value crops sample in 5 to 20 acre units. Up to 40 to 80 acres can be effective for uniform soils. IF YOU CAN SEE A DIFFERENCE, it will test differently. TAKE SPECIFIC SAMPLES so the range of difference is known to use judgment in varying treatments. DO NOT AVERAGE WIDE DIFFERENCES IN A SINGLE SAMPLE.
Confine problem samples to the specific area such as the one inch of soil next to a dying seedling. If salts are suspected always take separate specific samples from the same hole, in a top 6" and then separate 12" increments through the soil profile; to bedrock on 4' depth.
WITH SHOVEL remove a 1" thick slice from the smooth side of the open hole that goes from the surface (do not scrape off crust) through the root zone. With the slice on the blade of the shovel, rake the sides off with a knife, trowel or hands so a ribbon of the root zone soil 1 inch wide and 1 inch thick can be placed in a clean container, plastic is best. Repeat at random across area.
MIX THOROUGHLY the several representative slices, removing all foreign matter; roots, stalks, rocks, etc. Be sure the surface crusts are mixed in this sample as they can contain soluble fertilizer salts that can affect plants. Place in a bag (zip-lock) - identify sample. Fill out information sheet.
HOW MUCH? Send the lab at least 1/2 pint, but not over a pint of soil. Do not place paper with wet soil - paper decomposes.
HOW OFTEN? After each crop for optimum management or every 3 years.
FOR COMPOST or other organic material samples, send 2 to 4 quarts of hand grab samples taken at random around and in pile, to be a representative composite sample.
SOIL SUITABILITY TEST or problem evaluations should be sampled to 4 feet or bedrock in one foot increments Keep each separate. For long term evaluations repeat every 3 to 4 years.
SEND INFORMATION for each sample. HISTORY of crops, fertilizers, results, problems. CROPS TO BE grown and yield goals. IRRIGATION method. TYPE OF TEST desired: ( standard, micros, special, organic, etc.)
SEND payment with sample to help keep costs low. (Fill in the information entry sheet)