SWI 132.1.1 Seed Program
Specific Work Instruction
Official Seed Sampling

11.0 Seed Sampling

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This section applies for all seed lot sampling. Special requirements for sampling for the purpose of the issuance of an Orange International Seed Lot Certificate are included and indicated in bold text.

11.1 Preparation for Sampling the Seed Lot

The sampler must:

  1. communicate with the operator, grower, owner/manager of the establishment regarding the number of seed lots for sampling and their location in the warehouse;
  2. verify that the seed lot is fully accessible for sampling, subject to the exceptions provided in Section 11.5;
  3. refuse to sample when a seed lot:
    1. is not labelled;
    2. labelled for export only (Seeds Regulations, subsection 5(2)) unless an Orange International Seed Lot Certificate is requested or an official certificate of analysis from a government laboratory is requested;
    3. the seed lot is being sampled for an Orange International Seed Lot Certificate and exceeds the maximum lot size;
    4. there is evidence of tampering of the seed lot.

    Evidence that the seed lot has been tampered with includes:

    1. tags stapled to containers that contain other tags with contradictory information;
    2. tags contain information contrary to that printed on the container;
    3. torn tags or tags that appear to have been reused;
    4. bags are sewn once to close and another line of stitching is used to attach the tag;
    5. containers with broken seals.

      The ISTA Rules state the maximum lot size which can be represented by a single sample and an Orange International Seed Lot Certificate. The seed lot cannot exceed the maximum lot size stated. If the seed lot does exceed the maximum lot size, the seed lot will have to be broken down into seed lots of a size that meet the lot size requirements. Both the ISTA Rules and the EU Directives allow a 5% tolerance on the maximum lot size. For example, if the maximum lot size is 10,000 kg, the seed lot may not exceed 10,500 kg.

  4. verify:
    1. the crop kind for sampling;
    2. that the seed lot is labelled with a unique lot designation/number;
    3. that all containers in the seed lot are identified with the lot designation/number;
    4. that all containers are labelled with lot number, net quantity, name and address of the seller, packager or labeler, crop kind, grade name, and if applicable, variety name. If tags are affixed to a seed lot, the sampler must verify that the information on the tag corresponds to all the documentation. For the issuance of an Orange International Seed Lot Certificate, when the company prints the tags prior to sampling, the sampler must verify that all information printed on the tags is correct on every container;
    5. the size of the seed lot to determine the sampling intensity. There are no maximum lot sizes for domestic seed lots or OECD NFC lots;
    6. that the seed lot is sealed whether the seed is pedigreed or non-pedigreed seed when the seed lot is being sampled for issuance of an Orange International Seed Lot Certificate. The sampler must verify that the seed lots are sealed in a tamper-proof manner. When sampling for other official purposes (e.g., marketplace surveillance), the seed lot must be sealed when packaged in containers capable of being sealed such as bags of greater or less than 100 kg. The seed lot will be deemed to be sealed if the stitching that seals the bag opening also secures the tag to the bag.
  5. consult documentation related to the seed lot to verify lot size and identification (e.g., crop certificates, pedigreed seed declarations (Appendix XIX), blending certificates, certificates of analysis).

11.2 Sampling the Seed Lot

The following procedures must be used when sampling the seed lot:

  1. the sampling intensity must be determined as specified in Appendix II;
  2. before sampling the seed lot, the appropriate method for sampling based on the crop kind and the packaging of the seed must be selected;
  3. the seed lot must be sampled using the appropriate technique for the selected method or trier as described in Section 7;
  4. triers must not be inserted through labels or printed labelling on bags;
  5. the containers chosen for sampling are selected randomly based on the minimum number of primary samples required to obtain a representative sample of the seed lot;
  6. if selected containers are stacked on top of one another, sample containers nearest the bottom first and work upward;
  7. before sampling, ensure that container surfaces are free of debris that may contaminate the seed sample or the seed in the container;
  8. approximately equal amounts of seed are to be taken from each container sampled, or from each place in the container, or when sampling seed in bulk, from each location sampled;


    1. There are 400 - 25 kg bags in the seed lot. The seed lot is stored on 10 pallets each containing 40 containers. The sampler should randomly select three containers on each pallet for sampling. The sampling pattern should vary from pallet to pallet.
    2. When sampling containers more than 100 kg, the primary samples must be drawn, as applicable, from different locations or angles, in each container. In all cases, when sampling a seed lot of up to 15 containers, all containers must be sampled. The same number of primary samples must be taken from each container;
  9. the container/pail in which the sample is placed as it is drawn must be thoroughly cleaned at the beginning of the sampling procedure and after each sampling operation;
  10. the contents of each trier or handful, etc. is known as a primary sample. If the primary samples are uniform as described in Section 10.0, they are combined and form the composite sample.

    When a sample is being taken for an ISTA certificate and the primary samples are not uniform, the sampler should discontinue sampling, inform the client and request corrective action.

    The sampling may be resumed once appropriate corrective action is taken. When samples are being taken for marketplace surveillance and the primary samples are not uniform, the sampler should submit the sample and note the evidence of heterogeneity on the SSF (Appendix V). The seed sampler should take steps to determine the source of the heterogeneity and take appropriate compliance and/or enforcement actions;

  11. when samples are being taken for moisture testing, the sampler must take the moisture sample as quickly as possible after the completion of sampling as described in Section;
  12. when the composite sample is to be mixed and divided for the submission of the sample to the laboratory, the sample (large seeded crop kinds only) must be mixed and divided by an approved method as described in Section 13.0;
  13. the sample size submitted to the CFIA laboratory must meet the minimum quantities set out in Appendix III;
  14. if the sampler is conducting a purity analysis, the minimum sample sizes for examination and screening must be those indicated in Appendix VIII;
  15. the submitted sample must be forwarded to the laboratory in a timely manner;
  16. the sample must be stored in such a manner that the integrity and quality of the sample are not placed at risk. The sampler is to be in possession of the samples at all times. Samples for testing should never be left in the hands of the regulated party, except samples for export that are sealed in a tamper-proof manner by the CFIA sampler for shipping by the applicant;
  17. the container in which the submitted sample is to be placed must be labelled with:
    1. the inspection sample number;
    2. crop kind;
    3. variety name, (for all pedigreed seed; vegetables);
    4. lot number (must be stated for all pedigreed seed and OECD sampling);
    5. date of sampling;
    6. signature of the sampler;
  18. the sample must be sealed as described in Section 15.2.

A Checklist for sampling for Blue International Seed Sample Certificates and domestic purposes can be found in Appendix VI. A Checklist for sampling for issuance of Orange International Seed Lot Certificates can be found in Appendix VII.

11.3 Sampling Seed Packaged in Small Containers

When sampling seed packaged in containers of less than 15 kg for the issuance of an Orange International Seed Lot Certificate:

  1. the requirements set out in the ISTA Rules Chapter 2 must be followed. Containers must be combined to form sampling units not exceeding 100 kg. Seed tapes or seed mats, each with equal or less than 100,000 seeds can be combined to sampling units not exceeding 2,000,000 seeds;
  2. the sampling units must be regarded as containers for determining sampling intensity (Appendix II). The number of sampling units is always rounded up when there is a fraction;

Number of containers x the size of each container / 100 kg = Number of sampling units

the original containers must then be resealed or the seed placed into new containers, marked and labelled by the establishment under the supervision of an official seed sampler.

When sampling seed lots in containers smaller than 15 kg for other purposes:

The principles set out in the ISTA Rules Chapter 2 should be followed. In cases in which the integrity of the packaging will be altered at the retail level such as tins, packets, paper bags or moisture-proof containers, a sufficient number of containers must be opened and sampled until a sample of a sufficient size is obtained. The original containers must then be resealed or the seed placed into new containers by the establishment. In the case of small packages of herbs, vegetables and lawn and turf grass mixtures, a sufficient number of sealed packets should be taken as a sample.

If sampling of small packet (SPK) seed is requested by the Seed Section in the I-memo, the sampler must refer to the I-memo for specific sampling instructions.

11.4 Sampling Containers Greater Than 15 kg

For seed lots packaged in containers of up to or less than 100 kg in size, the sample must be obtained from sealed, labelled containers.

Each sealed container containing seed (e.g., poly bag, paper bag, tins, cartons, etc.) is considered to be a unit for determining the number of containers in a seed lot, not the numbers of pallets, etc. on which the seed is stored.

The sampler must verify that the containers selected for sampling, and those adjacent to the container being sampled, are clean and free from debris by brushing or sweeping any extraneous material from the containers and the area before inserting the trier. When sampling, the sampler should start sampling at the bottom of the pallet and work upwards. The sampling pattern should be varied from bottom, middle and top bags on the pallet, and between pallets, thereby reducing the likelihood of the sampling operation causing contamination. To facilitate diagonal sampling of standing bags of up to 100 kg, they must be laid flat. The bags may also be raised off the floor and placed on top of other bags.

The holes in jute or poly bags made by the trier must be closed by running the point of the trier across the hole a couple of times in opposite directions to pull the threads together and close the hole. When the hole cannot be closed by this method, suitable adhesive patching tape/label (CFIA/ACIA 0013, Appendix XVIII) is to be used. Such would be the case with paper bags. The patch must be signed and dated.

11.5 Sampling From Bulk Seed Lots Packaged in Containers of More Than 100 kg:

For seed packaged in bulk containers (mini-bulk bags), whether sampling for the issuance of an Orange International Seed Lot Certificate or marketplace surveillance, the sample must be obtained from the sealed, tagged/labelled container(s) using an approved trier (Appendix I) and sampling intensity (Appendix II) whenever possible.

Samplers wishing to take marketplace monitoring or variety verification samples may encounter situations in which sealed mini-bulk bags are not easily accessible or when sampling may pose a hazard. In these circumstances, there are two options:

  1. the establishment may make the bags accessible to the sampler; or
  2. the sampler may sample from the retained sample provided that the retained sample is of sufficient quantity to allow for this.

Industry, through the Canadian Seed Institute, has been advised of the need for increased retained sample sizes when accessibility of mini-bulk bags is an issue.

Note: COM or INV samples must be taken from the bags. Establishments continue to be required to provide reasonable assistance in making bags accessible for sampling for these purposes as required by subsection 6(2) of the Seeds Act.

For Marketplace Surveillance

When sampling:

  1. at an approved conditioner or bulk storage facility, where the seed is in containers such as a bin, railcar, truck box or a trailer; or
  2. non-pedigreed seed,

the sample must be taken from the:

  1. retained sample, if it is an officially-recognized sample, unless there is reason to believe that the retained sample does not represent the seed lot or is not available;
  2. bin, unless it is unsafe to do so; or
  3. static bulk lot.

When obtaining marketplace surveillance samples from bins, it may be necessary to find an alternate method of obtaining a representative sample. The sampler must follow prescribed sampling methods and procedures to obtain a sample that represents the lot. If the seed lot is not accessible, the sample may be taken from the retained sample, as indicated above. In addition, the sampler should note the following:

  1. when sampling a seed lot stored in a bin with a side access door, the sample is obtained using a double sleeved trier;
  2. when sampling a seed lot from the bottom of a hopper bottom bin:
    1. withdraw a minimum of 10 kg;
    2. obtain the laboratory's submitted sample (e.g., 1 kg) using the approved mixing and dividing method as described in Section 13; or
    3. if an approved dividing method is not available, the composite sample must be placed into a container (e.g., woven plastic bag) that can be sampled using an approved trier (Appendix I) and sampling intensity (Appendix II). For each of the above scenarios stated above or similar situations for the purposes of submission of the official sample, the lot size should be that quantity from which the submitted sample was obtained. The method of sampling should be as specified in Section 7 and the sampling intensities as specified in Appendix II.

When a noncompliance has been identified based on a sample taken using an alternate method, a sample that better represents the seed lot (the seed lot being that which is available on site) must be taken to determine the appropriate corrective action.

11.6 Sampling Unpackaged Bulk Lots

When sampling large lots from the stream or from flat-bottomed bulk bins, the sampler is required to take one primary sample per 700 kg. As there is no limit on domestic lot size or Not Finally Certified (NFC) OECD lots, this may result in extremely large composite samples that are not practical to divide using a riffle divider. In this situation, the sampler should place the primary samples in one or more large bags, mixing the primary samples to the extent possible as they are added to the bag. Once all primary samples are taken, the sampler should treat the composite sample as if it was a seed lot and take an appropriate number of samples for the size of the composite sample, sampling from different angles or locations within the bag(s).

For example, if the composite sample is 98 kg and in one large bag, three primary samples are to be taken. If the composite sample is between 100 and 500 kg, five primary samples are to be taken. These latter primary samples are then mixed and divided using the riffle divider method to obtain a working sample of the correct size. When submitting the sample to the laboratory, the sampler must include a detailed explanation of the sampling method used.

Alternatively, the VV sample for large OECD NFC lots may be obtained from the retained sample originally drawn by the RSE's sampler.

11.7 Sampling the Retained Sample

The method of sampling is to be determined by the sample storage method and the retained sample size at the seed establishment. Approved sampling equipment must be used to obtain the sample as described in Section 7 and Appendix I.

When the retained sample at the seed establishment cannot be sampled by use of approved sampling equipment, the sampler must mix and divide the retained sample of large seeded crop kinds only by using an approved mixing and dividing method as described in Section 13.0. When the sampler can neither draw a sample using approved sampling equipment nor mix and divide the retained sample, the entire retained sample is to be submitted to the appropriate laboratory for testing.

11.8 Sampling Seed Lots in Multiple Package Sizes

Samplers may need to sample a seed lot that is presented in mixed container sizes/types rather than in uniform container sizes/types. Depending on the purpose of the sampling and testing of the lot presented in mixed containers, the following direction should be followed.

11.8.1 Marketplace Surveillance Samples

One composite sample should be taken from the containers of the size/type that represent the largest part of the lot. The sampling intensity applied should be that which is listed in Appendix II for that portion of the lot only.

Example: If a lot is presented in 25 totes of 500 kg and 100 bags of 40 kg, then the part of the lot in totes should be sampled since it is the largest part of the lot; the sampling intensity that is used should be that which is required for sampling 25 totes of 500 kg.

It is assumed that the lot is homogeneous even if it is presented in mixed container sizes/types and that the largest portion of the lot is most representative of the seed that is offered for sale in the marketplace.

If only one container size/type is available for sampling (i.e., if other parts of the lot in different container sizes/types have already been sold), the sampler is only required to sample the part of the lot that is available even though it may not represent the largest part of the lot.

11.8.2 COM and INV Samples

The parts of the lot with different container sizes/types must be sampled separately using the sample intensity listed in Appendix II for each part of the lot. The composite sample for each part of the seed lot must be submitted singly as one sample and must not be combined with composite samples from other parts of the lot. Unique identifiers must be assigned by the inspector to the samples that represent unique parts of a lot; a separate certificate of analysis will be completed for each part of the lot assigned a unique identifier. The link between the samples and the parts of the lot should be reported by the sampler in the Comments section of the SSF.

The number of samples submitted for such a seed lot will equal the number of different size/type groupings of containers that make up the lot (e.g., if the seed lot is in two container sizes, then two samples must be submitted).

In cases in which the seed lot is in containers of one size but there is leftover seed at the end of the lot in a partially full container or a smaller container, this container is to be included in the lot and is treated as being the same kind of container. If the partially full or small container is in a seed lot with different container sizes/types, it should be considered as part of the lot that is in the smallest containers.

The uniformity of a seed lot is a requirement of a 'seed lot' as defined by the Seeds Regulations. The purpose of sampling and testing separate samples for each part of the lot is to enable verification of the homogeneity of the lot by determining whether or not the test results from the various parts are within an acceptable range of statistical variability (a tolerance) with each other. Should the differences between the samples be more than the expected statistical variation (out of tolerance), the remainder of the parts of the lot must be treated as individual lots, be assigned unique lot numbers, and be regraded.

11.8.3 EXP Samples

The ISTA Handbook on Seed Sampling, referenced in the ISTA Rules, states that different types of containers for a single lot may be indicators of lot heterogeneity. For seed lots exported from Canada that require testing according to the ISTA Rules, a CDN lot number must represent a lot of seed presented in uniform container sizes/types. As such, use of multiple container sizes/types for lots to be tested according to the ISTA Rules should not occur.

Should a sampler encounter a lot for ISTA sampling that is presented in multiple container sizes/types, s/he should not sample the lot until the lot is presented properly (i.e., the different container sizes/types are given different CDN numbers).

In cases in which there is leftover seed in a partially full container or a smaller container, this is considered the end of the seed lot and is treated as the same kind of container.

11.8.4 Authorized Exporter Program (AEP) Monitoring Samples

As part of the monitoring of Authorized Exporter (AE) samplers in the AEP, an inspector may be required to sample a seed lot that has been tested by the ISTA Rules or by the AOSA Rules for Testing Seed. The CFIA requires that all seed lots sampled by AE samplers be treated the same, regardless of testing by the ISTA or AOSA rules and, thus, imposes the same sampling requirements for lots tested by the AOSA rules as those tested by the ISTA rules.

Therefore, any lot sampled by an AE sampler and tested by either ISTA or AOSA rules must be presented in one container size and type only. If this appears not to be the case when an inspector is taking AE monitoring samples, s/he should investigate. If it is confirmed that the exported lot was made up of more than one container size, Seed Section should be informed and the AE must put in place corrective measures to prevent recurrence of this error.

Leftover seed in a partially full container or a smaller container should be considered the end of the seed lot and should be treated as being the same kind of container.

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