Sampling Guide for Plant Tissue Analysis

Collection and Preparation of the Sample

            When gathering the tissue sample in the field, be sure to use a clean container.  A plastic pail or a paper bag work best.  Never use a metal container to gather the sample as the metal may contaminate the sample.   

            To insure proper sample amount on young plants, collect approximately one pint of lightly packed material.

            If the plant samples have soil, fertilizer, dust, or spray residues on them, they will need to be cleaned.  A dry brush works well.  For stubborn residues, wipe the samples with a damp cloth or wash the samples with distilled or deionized water.  However, do not prolong the washing.

            Air-dry the samples.  Clean paper bags or envelopes work best to avoid contamination when mailing the samples to the laboratory. Never place fresh samples in a plastic bag.  Do not include roots with samples submitted for nutrient analysis.

Soybean Tissue

WHEN TO SAMPLE           PART OF PLANT TO SAMPLE                SAMPLE SIZE    

Seedling Stage                     All the above ground portion                      20-30 Plants

Prior to or during           The first fully developed leaves from the top       20-30  Leaves

initial flowering                

i

Corn Tissue

WHEN TO SAMPLE           PART OF PLANT TO SAMPLE                       SAMPLE SIZE    

Seedling Stage                     All the above ground portion                                  20-30 Plants

Prior to Tasseling                 The first fully developed leaves from the top       15-20 Leaves

From Tasseling to Silking  The leaves below and opposite the ears             15-20 Leaves

Common Mistakes when Sampling Crop Tissue

• Corn Silk has begun to brown
• Soybean is in full flower
• More than 10% of legumes are in bloom
• Cereals and Grasses are at flowering
• Storing Samples in Plastic Bags