Oregon State University

Frequently Asked Questions

We have prepared this information to answer basic questions about the OSU Seed Lab and seed testing. See the ISTA FAQ for additional information about getting ISTA Certificates.


General Information

What are the major services of the lab?

The major service at the lab is seed testing, which is used to determine the quality of seed. This is used for compliance with federal seed labeling laws, seed certification, Sod quality labeling, ISTA certificates, and other uses. In addition, the lab conducts applied research to improve testing methods and to assist industry customers. Hands-on workshops are also offered as educational events for seed industry customers.

What kind of samples does the lab test?

We test a broad range of samples, including official, certified, commercial, research, regulatory, and any sample pulled by seed growers, companies, etc.

Can the lab test samples from other states or countries?

Yes. The majority of samples come from within Oregon, but we can test samples from other states and countries. We have received samples from as far away as Alaska, North Carolina, Florida, Uruguay, and Australia.

What tests does the lab offer?

We offer a full complement of standard seed tests, including purity (together with a range of exams), germination, tetrazolium, vigor, ploidy, endophyte, species/cultivar identification, and many specialized tests. For more information on specific tests, please see the seed testing services page.

What testing rules does the lab use?

The testing rule used depends on the type of tests requested, and the destination of the seed. Rules we use include: AOSA (Association of Official Seed Analysts), ISTA (International Seed Testing Association), and Canadian Methods and Procedures for Testing Seed. Tests and evaluations can also be done for specific requirements, such as for Canada, Australia, Mexico, etc.

What species can the lab test?

The great majority of samples received are grass seeds, but we also test seeds of trees, cereals, legumes, oil seeds, flowers, vegetables, native species, shrubs and others. Given this diversity, we participate in several proficiency test programs and maintain a very large reference seed collection (herbarium).

Can I visit the seed lab?

The lab encourages visitors (seed growers, cleaners, shippers, students, and the general public) to come and see our operation. Please contact us to set the date and time and to arrange a tour guide.

What are the charges for our services?

The fees for testing services are available on the testing fees page. Fees for research depend on the type of research needed. Fees for educational events are specific to the event and will be announced when they are coordinated.

Do you offer volume discounts?

Yes.  We offer volume discounts for vegetable and flower seed germination testing.  The discount is proportional to the number of samples submitted: 50-99 samples 50% off; 100-199 samples 60% off; 200+ samples 70% off.  Please see our testing fees page or contact us for more information.

Sampling the Lot

Is the sample for Oregon Certification?

Samples for Oregon Certification can be obtained by authorized samplers of Oregon Seed Services (ph: 541-737-4513).  The sample is submitted in person by the sampler or through a secure mail service.

Is the sample for ISTA Orange International Certificate?

Samples for the Orange International Certificate (OIC) can be obtained only by samplers authorized by the OSU Seed Laboratory. The sample is delivered to the lab in person or by a secure courier.

Is the sample for ISTA Blue International Certificate?

Samples for the Blue International Certificate (BIC) can be obtained by anyone. All certification samples submitted to the lab by Seed Certification personnel or by private individuals qualify for the BIC, provided sufficient seed is submitted.

Where do I find sampling manuals? 

For detailed sampling procedures you may want to check the AOSA Rules for Testing Seed, ISTA International Rules for Testing Seeds, ISTA Handbook on Seed Sampling, American Association of Seed Control Officials (AASCO) Handbook on Seed Sampling, or the Oregon Seed Certification Service Guide for Certification Samplers and Taggers. You may also contact us directly.

Submitting Samples

How do I prepare a sample?

Samples are submitted in secure bags or envelopes. Each sample should be properly identified with the crop kind, tests requested, identification (lot or reference number), and treatment used. To avoid spillage in transport, place the sample bag inside a Ziploc or plastic bag.  Samples for moisture testing need to be submitted in a sealed Ziploc bag to avoid moisture exchange. Live plant materials for grow-out need to be submitted with wet paper towels to protect the root system, and transported using the fastest service. Using our order forms will ensure we get all the information we need.

How much seed should be submitted?

A minimum of 2500 seeds is required by both AOSA and ISTA for a purity test. Any bulk exam such as noxious or ISTA complete requires 25,000 seeds. Germination requires 400 seeds; TZ requires 200 for AOSA and 400 for ISTA. These are minimums; in practice at least 10% more seed is needed, and viability testing may require two or three times the minimum in some situations. For a complete set of common tests (purity, noxious, germ), the following are guidelines for common seeds. Please call us if you have any questions or need more specific information.

Suggested Sample Weights
Crop type Sample Weight
Small-seeded grasses (bentgrass, bluegrass) 4 oz (115g)
Large-seeded grasses (fescue, ryegrass, orchardgrass) 8 oz (230g)
Grains 2 lbs (900g)
Alfalfa and clovers 1.25 lbs (567g)
Large-seeded vegetables (beans, corn, squash, beets, etc) 2 lbs (900g)
Medium-seeded vegetables (brassicas, onions, spinach, pepper, tomato, etc) 8 oz (230g)
Small-seeded vegetables (carrot, celery, dill, parsley, etc)

2 oz (60g)

What is the best way to send it safely?

Make sure each sample is securely enclosed in a leak-proof bag, such as a ziplock. If using paper bags, make sure the corners do not leak seeds. Plastic bags seem to be more resistant to heavy handling. Pack the bags into a sturdy box and use packing material to keep them from shifting around. Put order forms or other identification and testing information in the box. Tape the box securely and send it to us.

Can I drop it off at the lab?

We welcome customers! Our hours are 8 to 5, Monday to Friday. If you plan to come during lunch (12-1), please call ahead to ensure that someone will be here to meet you. We also have an after-hours sample drop by the lab front door. It does not accept boxes, so please make sure that individual samples are each completely labeled.

Does the lab retain samples on file after testing?

The lab retains samples for a minimum of two years. Customers may request that excess seed be returned after testing, but the lab must retain the tested seed to comply with federal regulations. The file samples can be used for additional tests at customer request.

Speed of Testing

What is the regular speed of testing at the lab?

The regular speed in purity depends on the number of samples currently in process at the lab. Samples are tested in the order in which they arrive. Turnaround times range from few days in the slower season (winter and spring) to a week at the peak of the busy season (summer and fall). The Testing Flow Report, which is updated daily, has current information on how many samples are in the testing process.

Can I rush my sample?

We offer a rush service. Purity results will be available within 1-2 working days after the rush request is received. The rush charge is $109.00. When a rushed sample also has tests such as tetrazolium and germination, these are included in the rush service without additional charge to the customers.

Does my sample have to be pre-chilled?

Pre-chilling (or stratification) is a method of breaking or reducing dormancy and is required by the testing rules for fresh and dormant seed of many species. (See the table below.) Any deviation from the prescribed rule is noted on the testing report. If you wish a sample to not be chilled, indicate "no chill" VERY CLEARLY on the sample. Be aware that your germination results may be poor if your seed has a high level of dormancy and is not chilled.

Pre-Chill Guidelines for Common Crops
Crop Chill?
Ryegrass Current crop year (until approx. December)
Tall fescue, orchardgrass Current crop year
Bluegrass, bentgrass, fine fescues Current and previous crop years
Clover No
Grains No

How long until I get my germination test results?

The duration of a germination test is determined by the testing rules. It varies for each species and may be different for AOSA or ISTA rules. We do a count every 7 days on nearly all species (e.g. species requiring a 10 day final count do not get a 7 day preliminary count).  Germination is a natural process and determining if a sample has reached its full germination potential before or by the end of the prescribed time is at the discretion of the analyst. The table below lists AOSA germination durations for commonly tested crops.

AOSA Germination Durations for Commonly Tested Crops
Ryegrass 14 days
Tall fescue 14 days
Fine fescues 21 days
Kentucky bluegrass 21 days
Colonial and creeping bentgrass 28 days
Orchardgrass 21 days
Grains (wheat, barley, oat) 7-10 days
White and red clover 7 days


How long does TZ take?

Tetrazolium (TZ) results are usually available within 1-2 business days. Exceptions to this fast process are highly contaminated samples and some native species.

What can I do to ensure the quickest test results?

Several things can contribute to faster processing of any sample without ordering a rush: clear and accurate sample identification, ordering all tests at once, entering samples on the web, ordering Crop and Weed exam with the original purity so that it can be converted to UGS or Sod Quality report (for many species) on short notice.

Access to Test Results and Reports

Can I get early results?

Yes. We encourage our customers to download reports, access their results, and enter sample information online. Our goal is to reduce mailing and faxing. Our database has a secure customer login. This allows you access to test information and results as soon as they are available.

Can I get official test results online?

Yes. The Seed Services program can arrange on-site printing of test reports for those interested. Reports are available online to customers through a secure login. The reports are in the common PDF format.

Who can see my test results?

Only people or companies listed on the sample certificate or added as CC's can see your test results. We do not e-mail test reports as email is not secure enough for this purpose.

How do I get a report corrected?

Contact the lab immediately. We will investigate and issue corrected reports as soon as possible. If the correction is due to incorrect information being supplied to the lab, we may charge a fee. Note that some corrections for Certified seed, such as a change in lot number, may require sampler verification.

Can test results be converted from one system to another, such as AOSA to AOSA/EC (OECD)?

Yes, conversions can save time and money for our customers. Crop and weed exams can be converted to sod quality (SQ), UGS or Canada exams in most cases. For example, a crop and weed exam on Tall fescue can be converted to SQ, UGS or a Canada exam with no additional testing required. SQ can be converted to UGS certificates in most cases. A completed sod quality report on Tall fescue can be converted to an UGS certificate with no additional testing required. See the price list for conversion pricing information.

Conversion Information for Common Crops
Paperwork only - no additional testing required
Tall fescue Ryegrass
Kentucky bluegrass Tall fescue
Orchardgrass Rough bluegrass
Chewings and Red fescue All fine fescues
Additional testing required for conversion
Ryegrass: add'l 10 grams Kentucky bluegrass: add'l 5 grams
Rough bluegrass: add'l 0.5 grams  
Sheep and Hard fescue: add'l 5 grams  


Can I pay my bill with a credit card?

Yes. Please fill out the form and fax it to us. You can also call with your credit card information. Please do not ever email credit card information to us since email is not secure!

How can I tell if my bill is from the Seed Lab or Seed Certification?

At the top of the invoice, either Seed Laboratory or Seed Certification is shown in bold letters. 

Other Questions

Can I see the weed seeds or inert in my sample?

If you come to the lab we can show you any kind of contaminant found in your sample. If you cannot come, we would be happy to take a digital picture, side by side with the crop seed, and e-mail it to you.

Can I come watch my seed being tested?

To ensure that our analysts are not under any undue pressure, we do not generally permit customers to watch their own samples being tested. If you have any questions, please contact the laboratory manager to arrange a visit after the sample has been tested.

Contact Info

The OSU Seed Laboratory is an AOSA and ISTA member lab and is ISTA Accredited Laboratory US07.

3291 SW Campus Way
Corvallis, OR 97331
Phone: 541-737-4464
Fax: 541-737-2126

Hours: 8-5 Mon - Fri
Copyright ©  2017 Oregon State University