NC State Extension Publications


The North Carolina Department of Agriculture and Consumer Services (NCDA&CS) Cotton Seed Quality Testing Program began as a pilot program in 2020. The program was a huge success in its inaugural year due to the leadership of critical individuals in the NCDA&CS, the dedication and stellar efforts of our NCDA&CS inspectors, and the leadership from the North Carolina Cotton Producers Association.

During 2020, over 600 different seed lots were tested, and the NCDA&CS Cotton Seed Quality Database was accessed more than 600 times. The primary goal of this program is providing transparency that helps growers know the quality of the seed they purchase and make better planting decisions during periods of suboptimal planting weather. This is possible only through testing by an unbiased third party (NCDA&CS), which follows a stringent national protocol for evaluating both warm and cool germ.

The vast majority of seed lots tested in the program’s inaugural year resulted in very high quality seed, with 97% of lots tested with a warm germ of 75% or greater, and 87% with a cool germ of 50% or better. The percentage of seed lots with poor quality seed and/or stop sales warnings was very low. However, if one of these lots with poor quality seed should end up on your farm, the impact could be substantial.

Another goal of this program is to test as many seed lots as possible. It benefits all parties involved (especially you, as a grower) to have seed tested by NCDA&CS and the test results available before planting begins. This program is no longer a “pilot” program, for it gained momentum in 2021 and will continue into 2022 and beyond.

Initial Observations During the Launch Year

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In the years before the launch of the NCDA&CS Cotton Seed Quality Testing Program, seed quality had become a major concern of growers. Most growers did a much better job of sourcing seed quality information (warm and cool germ) from their seed company or dealer prior to planting, compared to the previous years. As found in the NCDA&CS Cotton Seed Quality Database, many growers sought NCDA&CS’s results for warm and cool germ at some point during the season. However, initial observations suggested that many growers:

  1. assumed that all seed lots, including the seed they had purchased, would have been tested by NCDA&CS at some point. Therefore, they didn’t need to take any action unless they experienced emergence problems, and
  2. assumed that NCDA&CS results for warm and cool germ would be the same or similar to the values provided by the growers’ seed company or dealer.

Both are false assumptions. With the first false assumption, NCDA&CS inspectors are only aware of seed lots that enter North Carolina if that information is given to them by the seed company or dealer. In many cases, however, the inspectors find other seed lots while they are working in a warehouse to collect samples from seed lots of which they have been notified. During the first few years of this program, there were nearly as many seed lots that NCDA&CS did NOT receive any prior notification of arrival as there were lots of which they were notified. Approximately 40% of the seed lots tested were lots that inspectors found while they were working in a warehouse to collect samples from previously notified seed lots.

Therefore, it is unwise to assume that NCDA&CS knows about the seed lots that you purchased, because this program is voluntary and not mandatory. This requires action to be taken by YOU, the grower, to ensure that your seed is tested. This also requires additional time if your seed is to be treated downstream, and/or if you want the NCDA&CS test results prior to planting, which is the only way to make the appropriate planting decisions.

With the second false assumption, in the large majority of cases, the NCDA&CS test results agreed when the seed company values for warm and cool germ were good. On occasion, there was a discrepancy. These are the situations that truly matter, especially if the seed quality is poorer than advertised or labeled. Therefore, it is unwise to assume that seed company results for warm and cool germ are equal to those of the NCDA&CS. This does not suggest that seed company values for warm and cool germ are misleading or false. This might reflect the possibility that the NCDA&CS tests are more likely to be collected much closer to planting time, and are likely to be more predictive of field performance. Therefore, you need to ensure that the seed you purchase has been tested by NCDA&CS, with results available ideally before planting. This also requires action to be taken by YOU, the grower.

Official versus Service Samples

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There are two types of samples for which cotton seed can be collected and tested by NCDA&CS.

  1. Official samples are regulatory samples collected by NCDA&CS inspectors from multiple bags with a stringent protocol, and most importantly, from unopened seed bags or containers, prior to any downstream seed treatment. Official samples are the only samples that can be used in seed complaints or arbitration through NCDA&CS if you experience emergence, vigor, or stand establishment problems in which seed quality is suspected to be poor or not as advertised. These samples must be collected by NCDA&CS inspectors, and cannot be collected by growers, Extension agents, specialists, or consultants who cannot collect or submit a sample to be qualified as “official.”
  2. Service samples can be collected by NCDA&CS inspectors, or anyone else, and/or are collected from bags or containers that have already been opened or when the seed has already been treated downstream. After a bag or container seal is opened, the chain of custody is broken and cannot otherwise be established. Service samples provide the same information as official (regulatory) samples, which is pertinent information that you need to make adequate planting decisions, but they do not have any merit in seed complaints or arbitration through NCDA&CS if you experience problems.

Both types of samples provide equally useful information that is needed during planting season, but only the official samples can be used in arbitration if quality issues are suspected. It is in your best interest to have an official sample on file for your seed lots in the NCDA&CS Cotton Seed Quality Database, although a service sample can also provide equally important information for planting decisions. Since inspectors must collect samples from multiple bags, you cannot simply leave one bag unopened for an official sample through NCDA&CS testing.


Skip to Logistics

Substantial time is needed for this process to flow properly and for this critical information to be on-hand prior to planting. Waiting until two weeks before planting to begin thinking about this, making phone calls, or trying to source this information is far too late. Our NCDA&CS inspectors and the NCDA&CS Seed Laboratory are committed to this program and work tirelessly to make it run smoothly for all involved. However, they do not have unlimited resources, and they cannot perform miracles. The warm and cool germs tests require twelve days to be completed. You should also consider the travel time for the inspectors to travel to the warehouse where your seed arrives, given the fact that they are receiving calls simultaneously from multiple dealers’ warehouses from all over the state. Consider the time required for collecting samples with the strict protocol, the packaging and handling of these samples, the shipment time to the NCDA&CS Seed Laboratory, the time needed for preparing these samples, the space limitations within the germinators, and the time required to evaluate the test results, which are both quantitative and qualitative. The NCDA&CS personnel are trying their best to accommodate every cotton grower in North Carolina. In addition, your dealer needs time to downstream-treat seed prior to planting, if you choose to have your seed treated locally. Initiating your responsibilities as a grower in early April is far too late. Your responsibilities are the easiest of all and should begin in January or February.

Your Roles and Responsibilities as a Grower

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Growers’ responsibilities are the easiest of anyone involved in this program, and they are designed to benefit you, the grower. A little effort on your part can go a long way in reaping the value of this program. Here are your responsibilities:

  1. Make sure you are on the NC State Extension Cotton newsletter list, or receive our newsletters from your local Extension agent or social media platforms. In each of the Planting Conditions newsletters that are released during planting season each year, there will be a link to the NCDA&CS Cotton Seed Quality Database. This database can also be found on our NC State Extension Cotton website, under “Calculators and Decision Aids” on the left-side toolbar or directly at the NCDA&CS Cotton Seed Quality Database.
  2. Make your variety decisions reasonably early and commit to that purchase. The results of the North Carolina On-Farm Cotton Variety Evaluation Program and NC State Official Variety Testing are always discussed during winter county cotton meetings. All variety performance data can also be found in the NC State Extension Cotton Variety Performance Calculator, which can also be found on the NC State Extension Cotton website under “Calculators and Decision Aids.” You should also decide what proportion of your seed will be treated upstream or downstream, so that subsequent plans can be made with your dealer.
  3. Notify both your seed company representative and your local dealer that you wish to have an official sample collected by NCDA&CS for all seed you will purchase and that you would like the results available before you intend to begin planting. This communication should be done sooner than later, although you will also need to communicate frequently with your dealer or seed company on progress toward this goal throughout the winter or spring until planting time. In addition, your local dealer needs to know if your seed is to be treated downstream so that they can plan accordingly as well. This will ensure that samples are collected by inspectors before the beginning of downstream treatment.
    Time is needed to downstream treat seed, and it is only fair to provide your dealer with ample notice of your needs. You can request that your dealer contact NCDA&CS to inform the inspectors of the arrival of your seed, or you can inform the inspectors directly. Frequent communication is needed by everyone. Please do not wait. Start all necessary communications in January or February, and frequently from that point through the planting season or until you receive all information about your seed.
  4. As soon as your dealer can provide this information, or as soon as your seed arrives at your dealer’s warehouse or your shop, it is important to document all pertinent information for each seed lot that you purchased. This can be as simple as taking a picture of the tag on the seed bags. The most important piece of information is the lot number. Make sure NCDA&CS knows the number and has collected samples from that lot. You can access the NCDA&CS Cotton Seed Quality Database to view the results. Other important information would include seed size (number of seed per pound), seed treatment, and origin.
  5. Access the NCDA&CS Cotton Seed Quality Database and document the results for warm and cool germ for your lot numbers. Use this information together with the NC State Extension Cotton Planting Conditions Calculator to make the best decisions possible. This calculator is also accessible on the NC State Extension Cotton website under “Calculators and Decision Aids.” If the database states that your lot number has not yet had a sample collected, contact Brian Bowers at NCDA&CS immediately (919-707-3756; Brian will arrange for an inspector to collect a sample as soon as reasonably possible. Remember that bags and containers cannot be opened, and the seed cannot already be treated for it to be considered an official sample. A service sample is still possible and necessary if any bags have already been opened or if the seed has already been treated downstream.

Why is This Important for You?

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If we are called to help you with an emergence, vigor, or stand establishment issue, during or after planting season, the first thing we will request from you is the NCDA&CS Cotton Seed Quality Test results for the lot number in question. We will help you to the best of our ability, but without the NCDA&CS test results, there is little we can do. This program brings a great deal of value to growers. Official samples provide the most value because they can be used in complaints and arbitration, although service samples also help with planting decisions as effectively as official (regulatory) samples. In cases where seed quality may be less than ideal but is still legal for sale, the test results will help you only if you have the results on hand before planting so that you can make the best planting decisions possible. Below are several real-world examples from the first year of the program.

In concert with the program, there have been several research studies initiated at NC State with a primary focus on cotton seed quality. The ultimate goals of this research are providing a better understanding of cotton seed quality, refining quality testing for improved predictability of field performance, and developing practical tools and procedures for the cotton industry to use in evaluating cotton seed quality. Below are photos and preliminary results from some field research that began in 2020.

Photo shows better seedling growth with higher levels of cool germ

Figure 1. Effect of cool germ on seedling vigor.

Graphic shows that the lot number with better cool germ had significantly higher yield.

Figure 2. Effect of cool germ on lint yield during 2020.


Scenario 1. In many cases, we may think that seed quality (warm and cool germ) primarily influences stand establishment. However, after we achieve a good stand, then we are good to go. In many years, especially those with favorable planting weather such as 2019, that may be the case because the small differences in seedling vigor may disappear after cotton reaches the 4 to 5 leaf stage. However, the 2020 planting season was quite different and was much worse overall because poor planting conditions lasted throughout the entire planting season. Figure 1 illustrates the visual difference in seedling vigor between two lot numbers of the same variety, which were identical in warm germ (87%, a good warm germ), but vastly different in cool germ (44% or poor cool germ on the left, and 67% or good cool germ on the right).

Although planting weather was largely uncooperative during that 2020 season, it is important to note that these plots were planted at the best time (May 15) prior to our first crop insurance cutoff date (May 25), when the 5-day heat unit accumulation after planting was nearly ideal. This period was followed by a cooler spell, which lasted through the season. Conditions prior to this date were very poor, and rains prevented further planting soon after May 18, but before the crop insurance cutoff of May 25. Although that planting season was an anomaly, it is common to have some periods similar to 2020 in other planting seasons. Figure 1 clearly illustrates the distinct difference in plant vigor between the two seed lots, even when an ideal stand was established with both lots. The differences in plant growth continued well into the season and were reflected in lint yield as seen in Figure 2, where the lot number with better cool germ resulted in significantly higher yields compared to the lot number with a poor cool germ. If the seed quality of these two lots had been known by a grower, we would have advised planting only the lot number with poor cool germ during a period with adequate heat units and favorable forecasts for a longer term.

Scenario 2. The second scenario is also a real-world example. Two lot numbers of the same variety arrived at a grower in North Carolina. Lot #1 had a warm germ of 92% and a cool germ of 82%, which is exceptional seed quality. Lot #2 had a warm germ of 72% and a cool germ of 42%. Both were legally for sale in North Carolina, although the latter has questionable seed quality that should only be planted in certain situations. Based on this information, Lot #1 could be planted at essentially anytime during the planting season that was acceptable for planting cotton. Of course, we would not advise planting cotton with any level of quality when the 5-day forecast predicts little to no heat unit accumulation. Whenever possible, we should avoid planting when conditions are either “marginal” or just “adequate.”

Depending on a grower’s acreage, the percentage of acres already planted at any given time, and the time remaining for planting before crop insurance deadlines, some growers may be forced to plant in less than ideal conditions, such as “marginal” or “adequate” conditions. This is common for large acreage growers in most years. In the case with less than ideal conditions in the 5-day forecast, only Lot #1 should be planted, given its much higher cool germ than Lot #2. In ideal conditions, such as 50 or more heat units predicted in the 5-day forecast, either lot number could be planted because cool germ is not as important when planting in ideal conditions. However, we would advise increasing the seeding rate for Lot #2 by 10% to 20% to account for a slightly low warm germ, even in ideal conditions. Lot #2 should not be planted in less than ideal conditions, although both lots are acceptable in ideal conditions when the seeding rate adjustments are made with Lot #2.

In summary, given that these two lots had very different seed quality, we would have offered very different recommendations for when and how they should be planted. The hidden secret here is that these two lots had the exact same Lot #. The warm/cool germ values for Lot #1 were provided to the grower by the seed company. The warm/cool germ values for Lot #2 were determined by NCDA&CS through sampling and testing. We are not implying that the seed company’s germ values are misleading. We are stating that NCDA&CS’s sampling is conducted closer to the actual planting date, and their results are likely to be more predictive of true field performance. In the majority of cases throughout 2020 and 2021, the seed company values and the NCDA&CS values were similar. However, the few discrepancies matter the most if that seed ends up on your farm.

We encourage all growers and dealers to join our seed companies in taking an active role participating in this program. The earlier you act, the smoother this program will be. Please remember that conversations should start during the winter months (January or February) and not later. Do your part, and reap the rewards.


Associate Professor, Extension Cotton Specialist
Crop & Soil Sciences
Professor, Cotton and Industrial Hemp Extension Specialist
Crop & Soil Sciences
Assistant Commissioner of Agricultural Services
Director, North Carolina Department of Agriculture and Consumer Services
Plant Industry Division
Associate Professor, International Agriculture
Crop & Soil Sciences

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Publication date: May 27, 2022

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