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Seed Tags - Seedtests
How to read a seed tag.

All seeds require a current seed analysis test in order to be sold via the seed industry. The ergot seeds above are an example of seed that a proper analysis will classify as "inert seeds". Basically all seeds tested are concerned with two primary test results; Those results covering the Seed Purity and Germination (See explanations below). All other items reported by a laboratory are derived from these two analysis areas, and further explain to the consumer the aspects of quality and dependability concerning one particular seed lot.

Aspects of a Purity & GerminationTest:
Listed below are the various terminology used within a test report to explain the analysis technicians findings on a particular sample of seed. See a Seed Analysis copy of an actual Bahiagrass test. This reporting is generally reported using a Seed Tag on each bag of a particular lot. The Tag reports the percentages that the seller is representing the seeds to have. It generally is lower than those reported on the actual laboratory test, however sometimes it is reported the same. It would be illegal to report higher percentages than actually found.

• What is a Lot Number?
• What is the Kind?
• What is the Variety?
• What is a Lab Number?
• What is Pure Seed (Purity)?
• What is Inert?
• What is Crop Seed?
• What is Weed Seed?
• What is the Date Recieved - Date Reported?
• What is Noxious Weeds?
• What is Hard Seed?
• What is Dormant Seed?
• What is Total Germination?
• What is PLS - Pure Live Seed?
• What is Sellers Name?

A lot number is a control number placed on the seed package by the packager of the seed. It identifies the particular batch of seeds through other records kept by the packager of the seeds. The number is placed on each package (bag) of seed that is a part of the same lot (or batch) of seed. The lot number is used to provide control and tracking over the seed, and to connect with the specific seeds, the analysis test results obtained from a representative sample of the lot.

Kind refers to the particular type of seed that are tested. For instance on a corn seed test, the kind (of seed) would be Corn. On Bahiagrass it is Bahiagrass seed. Usually the common name is used rather than the scientific name.

Variety refers to the specific hybrid, selection or strain of the growing plant. For example: Kind=Corn Variety=NK701 would identify the seed as a specific hybrid of corn seed. In Bahiagrass seeds the varieties are fewer in type, with most commercially grown seeds consisting of "Argentine", "Pensacola", or "Tifton 9 Pensacola"

The lab number is the "control number" that the laboratory assigns to the particular sample of seed for tracking purposes. Because the same seed lot can have many different tests performed over time, it is necessary to have a way of identifying multiple tests for the same lot number. Also the lab number facilitates the laboratories record keeping.

Purity is the first important "data" concerning the particular lot of seed. It reports the percentage of actual seed that are contained in each pound of seed. The total purity of a lot is composed of Pure Seed, Inert, Weed seed and Crop seed. All four of these figures must total 100%. Pure seed is the % of the sample that contains fully formed seeds, that from visual appearance are not damaged. Many varietiesof seed have a "standard" percentage in which they are not normally sold if they fall under that percentage.

In those cases, the packager must re-condition the seeds to improve the Pure Seed percentage and thus make the lot acceptable for sale. The actual percentage that the Pure Seed must be varies with both the type and variety of seeds. For instance Argentine Bahiagrass is sold with percentages running from 70% up into the 90's%. While Pensacola Bahiagrass is normally 95% or higher. In many cases it is economically not feasible to process the seed to a higher Pure Seed percentage. And in most cases, as long as you take into account the actual Pure Seed percentage, it has no affect on the actual seeds that do grow.  Seed PLS below.

The second part of the Pure Seed percentage... Inert is the percentage of non-viable inert material. This consists of many things such as, sand, plant material, broken seeds, rock, trash, or any material that is not actually seeds. It reflects both the characteristics of a particular seed variety in addition to the degree to which the seed lot has been professionally cleaned.

The Crop Seed percentage is total percentage of mature, sound seeds OF OTHER CROPS found in the representative sample tested.  These may or may not be objectionable seeds depending on your use for the primary kind of seed.

The Weed Seed percentage is the percentage of weed seeds found in the representative sample tested.  Usually the testing laboratory will also identify the weed seeds found and list them by name.  This information is not usually reported on the individual seed tag attached to the product bags.  Laws within each state determine the percentage of weed seed allowed in seeds for sale within a specific state.   Generally this percentage is limited to 1% to 2%.  Of course you want as weed-free percentage of seed as possible, but in some cases it is impractical to commercially remove all the weeds.  Other weeds contained in a lot may not be that objectionable as many times they are already present in your particular soil location.

The date reported is the date that the test sample germination and purity results were completed.  For most marketing uses, a test must be current within 6 months of the date of sale.  Specific state and federal laws determine the test date range allowed for sale of seed products in each particular state.

The percentage of noxious weeds is number and kind of Noxious weeds found in the representative sample submitted to the laboratory for testing the particular lot of seed.  By Noxious, that term does not mean the seed are bad or poisoned, but simply is a report based on the list of seeds that individual states have found to be "objectionable".  A seed that is noxious in one state, may not be in another.  Also a seed that is noxious in one state can also be a normal seed, grown and marketed in a different state.  Seeds can also be both a marketable crop seed and a noxious weed in the same state.  Most times the noxious classification is based on how objectionable that particular seed is in a major crop grown in the specific state.  What may be considered "objectionable / noxious" to growers in one state, may not be so in another state.

The dormant seed percentage is the percentage of seed that during the actual test in the laboratory did not germinate and produce a sprout, but appear to still be sound, alive seed based on standard testing procedures for the particular kind of seed.  By hard it means that the seed is still sound and firm under pressure and does not appear to have started to rot during the time frame observed within the normal germination period for the specific kind of seed.  Eventually most of the hard seeds should germinate.

The dormant seed percentage is the percentage of seed that during the actual test in the laboratory did not germinate and produce a sprout, but appear to still be sound, alive seed based on standard testing procedures for the particular kind of seed.  These "dormant" seed are a natural occurrence in many grasses and other seeds and are natures way of preserving the species against the chance of abnormal weather conditions at any one moment in time.  Eventually most of  these seeds should germinate as both time and more favorable weather / soil conditions occur..

The total Germination is the percentage of all seeds, active germinable seed, dormant seed and hard seed that are in the particular lot of seed. This is the % of seed when all conditions are favorable over time for you particular kind of seed should germinate.  To obtain this figure you add the rates found for the three components of germination.  For most seeds it is in the 75 to 90 percent range.   Laws prohibit selling seeds below certain germinable percentages, depending upon the particular kind of seed.  Different seed kinds (and varieties) have different germination rates.

The sellers name is the person / company responsible for the seed. This person may or may not be the actual grower of the particular seed.  It is simply the last person/company who took possession of the seed and legally tagged (and perhaps tested) the seed for sale on the market.

Pure Live Seed (PLS) is a combination % of the Pure seed percentage and the Germination %.  For instance if you have a purity of 90% and a total germination of 80%, you have a lot of seed with a PLS of 72%... (PLS=Germination% TIMES Pure Seed%)  This shows you the percentage of usable seed (72%) that will grow for you in the particular lot.  Some seeds are sold and marketed based on the PLS % for the particular lot, in the seed industry.

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