Nicolette Rusch SST Lab Manager, Eurofins BioDiagnostics

Occasionally, after I send a results report out to one of our customers, I will receive a response back indicating that the recipient doesn’t feel our test results accurately reflect the quality of the seed lot that they produced. Routinely my first response is, “How was the sample that you submitted obtained?” If proper sampling techniques were not followed and the seed sample does not reflect the bulk or bagged seed lot, then the QA test results are meaningless!

When you do not accurately sample your seed, you are potentially misrepresenting the quality of the lot and could be violating your customers’ trust. By only grabbing seed from the top of the bag, you are not getting a representative sample of what is in the entire bag. It is crucially important for seed samplers to make sure they collect a sample that accurately represents the entire seed lot.

Both the AOSA Rules and the AOSCA Handbook specify how many subsamples are needed for various crops and container sizes. Every seed sampler should be following these guidelines when taking samples.

When a 2-pound sample is tested to represent several thousand pounds of seed, even small sampling errors can seriously distort the validity of test results. There are established guidelines to indicate how many samples are needed.

If you just reach in and take a handful of seed from the top of each container, you are not getting a representative sample. You may have sampled the right number of containers, but the samples are still not representative of the entire seed lot. A phenomenon can occur during storage or movement of seed where lightweight seed, oddly shaped seed or seeds with differences in moisture content can cause differential settling of seed in bags or bulk containers. Grass seed mixtures are especially prone to segregation during handling. Heavier and larger seeds can segregate from lighter and smaller seeds. Thus, it is important that seed samplers draw from the full width of the seed storage container.

So, to gain a true picture of your seed quality, remember that proper seed sampling is the first step in an accurate estimate of your seed quality.