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We test all Ag crops, grasses, natives, forbs, vegetables, flowers and shrubs according to AOSA Rules for Testing Seed.


In seed testing, the emergence and development from the seed embryo of those essential structures are indicative of its ability to produce a normal plant under favorable conditions for the kind of seed in question. Four reps of 100 seeds are planted. Comments listed below the germination provide the customer with additional information such as abnormalities and fungi observed during test. Definitions of these remarks are defined later on this page.

Tetrazolium (TZ)

The TZ test provides a quick estimate of seed viability (ALIVE). Seeds are allowed to imbibe water before being cut or pierced through the embryo. They are then placed in Tetrazolium chloride which reacts with any respiring tissue, staining it red. The TZ test is also used in determining dormancy in Native Species.


Often called a Mechanical Purity, this test determines the percentage by weight of the submitted sample. It is divided into 4 parts: (1) PURE SEED - the kind of seed being tested. (2) Other Crops (OC) - contaminating pure seeds that are considered to be crops. (3) INERT - any component that is not considered a seed such as chaff, soil, sticks etc. (4) WEEDS - contaminating pure seeds that are recognized as weeds by law, regulation or general usage.

Noxious / Special Noxious

A sample is examined for noxious weeds. The amount of seed examined is by weight and is determined to be 25,000 seed units. When a Noxious exam is conducted we are looking for weeds that are considered noxious in any state excluding Hawaii. A Special Noxious exam can be requested if only a specific state‚Äôs noxious weeds are to be determined.  

Undesirable Grass Seed Search (UGS)

Similar to the Noxious exam. The UGS exam expands the noxious list to include 10 more species when testing Turf grasses. UGS comes standard with a Noxious exam on all turf grass samples unless specifically excluded by the customer.

Seed Count

Determines the Seeds per Pound.


Vigor Testing COMING SOON!

Determines the speed and uniformity of germination, especially under favorable conditions.

Cold Test

A stress test that exposes seeds to cold, wet conditions before being allowed to germinate in favorable conditions.

AA (Accelerated aging test)

A type of stress test that exposes seeds to high temperatures and high relative humidity for a set period of time.

Herbicide Bio-assays COMING SOON!

Includes the use of an herbicide to screen for trait and non-trait seedlings.

Canada Rules

Sample will be tested according to Canada Methods and Procedures. ISTA Rules Sample will be tested according to the International Seed Testing Association.

Other Determination

We strive to provide you with as much information as possible. If there is a test you would like to have done that is not listed please list your request under other requests.

Pure Live Seed (PLS)

Viability multiplied by Purity percentage divided by 100. Used mainly on Native Species.

Hard Seed

Seeds which remain hard at the end of the prescribed test period because they have not absorbed water due to an impermeable seed coat.

Dormant Seed

Viable seeds which fail to germinate when provided the specific germination conditions.

Seedling Abnormalities

A seedling that does not have all the essential structures or is damaged, deformed or decayed to such an extent that normal development is prevented.

(IR) Insufficient roots
(SS) Stunted shoots
(SDH) Short, damaged hypocotyls
(SL) Shredded leaves
(WH) watery hypocotyls
(DS) Decayed seedlings (caused by fungus)

Fungi examples:
(RH) Rhizopus spp.
(FU) Fusarium spp.
(AF) Aspergillus flavus
(AN) Aspergillus niger
(PE) Penicillium spp.
(AL) Alternaria spp.

* If one of these conditions is noticeable in the sample it will be noted in small case initials. If the condition causes a major drop in germination it will be noted in upper case.

Fax: (605) 729-2001
Phone: (605) 729-2000
340 N. Main Ave.
P.O. Box 100
Bridgewater, SD 57319