Agricultural Soil Testing For Lime and Fertilizer Recommendations
A good representative soil sample is the basis for a good soil test. Soil testing helps in determining soil nutrient levels and deficiencies in your soil and provides a basis for wise use of fertilizer and lime. Test results obtained from the regular soil test include: current pH, Phosphorus, Potassium, Calcium and Magnesium levels; plus fertilizer and lime recommendations, based upon what is to be grown.
Garden trowel or spade, sampling probe or soil auger
Plastic pint size sandwich bags
Taking the Sample Soil samples may be taken at any time during the year when temperatures (lack of frost) and moisture conditions permit.
Determine the area(s) you will be sampling. No larger than 10 acres per sample is recommended.
Using a trowel, probe or other sampling device, take 15-20 samples consisting of vertical columns or cores of soil approximately 1/2 - 1 inch square in cross section to the depth needed.
Avoid sampling unusual areas unless such locations are sampled and packaged in a separate soil box. Such areas may cause inaccurate test results that would not be representative of the whole area being sampled.
Sample in a random pattern throughout the area to be sampled. Place the 15-20 soil samples in the plastic pail.
Preparing & Packaging the Sample When you have finished taking all 15-20 samples, mix the soil in the pail thoroughly.
If the soil is very wet at sampling time, it may be necessary to partially air dry the sample in order to obtain an adequately mixed sample. Do not use artificial heat, such as an oven, to dry the soil.
If the soil is very dry at sampling time, it may be necessary to crush the soil cores and then mix.
After the sample is thoroughly mixed, label a pint-size plastic sandwich bag with the field number or other identification and fill the bag with soil from the pail and seal. Remove stones, plant roots, leaves, worms, insects, or other non-soil matter from the soil in your bag.
If you have a soil sample box, place the bag in the sample box. Follow the instructions below for completion of the accompanying “MSU Soil Test Information Sheet”.
On the sample box write your name, address, sample number (1, 2, A, B or whatever designation is meaningful to you), and county. It may be easier to write this information on the box BEFORE filling it with soil. It is not necessary to complete the remaining information below sample number, as this will be listed on the MSU Soil Test Information Sheet.
Now, complete the MSU Soil Test Information Sheet appropriate for your sample(s). This form is used for farm or field crops; CRP and wildlife forage seedings; commercial landscape, nursery or similar operations. This form is not used for home lawns, gardens or landscaping.
Complete the identification section at the top of the form. If you have any comments that may help in the analysis of your sample(s), list them in the area at the top marked COMMENTS.
Next, fill in the columns on the bottom of the sheet, as follows:
GROWER SAMPLE IDENTIFICATION: write the sample number(s) or other identification for each sample from your sample box(es).
PREVIOUS CROP: List the code number of the last crop grown in that field, from the list on the back of the form.
1ST OR 2ND YEAR CROP & YIELD GOAL: In the next two sets of columns list the code number of the next two crops to be grown, from the list on the back, and yields is bushels per acre or tons per acres.
PREVIOUS LEGUME % STAND: List the percentage of any previous legume crop, if applicable.
TILLAGE DEPTH: List how deep you will be tilling the field.
SAMPLING DEPTH: List how deep the soil was sampled, in inches.
ACRES REPRESENTED: List the acres of the field in whole numbers. Round tenths of acres.
MANURE APPLIED: If manure was applied to the field, write in the amount applied in gallons/acre.
IRRIGATED: Mark whether irrigation has been used on the field, Y for Yes; N for No.
TESTS REQUESTED: Check the box with the "1" to indicate this is a standard soil test.
FOR CORN SAMPLES ONLY: Also complete the “Price of N” and “Price of Corn” blanks in the upper right corner of the sample information section.
Delivering Samples to Testing Lab If you purchased a sample box and the information sheet from the Conservation District and paid to have the District submit your samples to the lab, bring the sample box and information sheet to the District Office.
If you purchased a sample box without mailing by the District, you can mail the sample(s) and completed information sheet(s) to the soil testing lab yourself, following the “Procedures For Mailing Samples” panel on the sample box.
Sample Results Once soil samples have been analyzed a soil test report is prepared and will be mailed or e-mailed directly to you. Sample results may take anywhere from 2-5 weeks, depending upon the time of year, and volume of samples to be analyzed by the lab.
If you have any questions about taking a soil sample or filling out the forms, call the Conservation District at 734-761-6721 ext. 5.
Washtenaw County Conservation District Copyright 2016