Seed-counting machine


Seed-counting machine
Data Count&Fill S60 seed counter.jpg
A seed counter and packager
ApplicationCounting seeds

Seed counting machines (Seed counters) count seeds for research and packaging purposes. The machines typically provide total counts of seeds, or batch sizes for packaging.


The first seed counters were developed to count legumes or other seeds which were larger.[1] Traditionally, the seed packaging industry packed seeds by weight using weighing scales. Seeds were packed by weight while sold as units. In order to assure the correct quantity of seeds, seed distributors added a safety margin to the packed weight. This is rather like a Bakers' dozen. It assuages concerns about short weighting or under counting. It is an attempt to assure customer satisfaction and expectations. It may enhance customer relations and build good will. This safety margin obviously increases costs, and results in loss of some profit. The seed counter is a uniquely appropriate solution for items that are sold by units as opposed to weight.[2] The accuracy helps lessen the need to build in safety margins for quantity; and the costs of the machinery can be more than paid for by reduced labor costs.[3]


1928 United States Department of Agriculture publication regarding seed counters

Originally people did seed counting by hand, or used a trip board. The first seed-counting machine was the vibratory mechanical seed counter. Modern day electronic seed counters are faster and more accurate.[4] A color-image-based seed sorter was developed which can sort various things by their color.[5]

In 1929 the US Bureau of Plant Industry worked with several seed companies to perfect a seed counter.[6] In 1962 an electric seed counter was developed by the USDA's Agricultural Marketing Service. The electronic counter operation involved the a vibrating the seeds so that they move to the edge of the counting machine.[1]

The machine will pay for itself over the labor intensive tedious task of manually counting seeds, which is necessarily characterized by human error. By contrast, the new devices, even in the early 1960s, boasted increased speed and “about 1 error in counting 10,000 seeds counted.” The accuracy helps lessen the need to build in safety margins for quantity; and the costs of the machinery can be more than paid for by reduced labor costs.[3]

In the 1970s other electronic seed counting advancements included an electric eye to count the seeds. Seed counting still involved vibrating the seed, but now the seed would fall through a seed hole.[7]


At one time, the methodology included use of vacuum tubes, vacuum pumps, a light source and a photo transistor. The size needed to be adjusted so only one seed passes through at a time. To be useful, batch counters need to be commercially available. A single preset count facility is a plus, as is “adequate count capacity, the ability to provide external power supplies and [control of] ... the means to stop the picking up and counting of seeds.”[8]

For example, the “Contador electronic seed counter is a valuable instrument that satisfies a spectrum of seed counting requirements.” Useful features include:

  • automatic variable counting speed “depending on the size of the material/seeds to be counted,” which optimizes counting capacity usage, minimizes counting time, and maintains counting accuracy, thereby minimizing over counts.[9]
  • Manual and automatic speed adjustment and shut off.[9]
  • Recognition that the hopper is empty or nearly so.[9]
  • Signal filtering, so that smaller particles ('noise) are disregarded.[9]

In commercial operations, it is important for the counter to be automatic and accurate. For example, one commercial counter is capable of measuring the hundredth/thousandth grain weight for seeds, tablets, pearls, and small components. It adopts far-infrared area sensor, and a large enough photosensitive area, "suitable for the sensitivity of all crops (millet-peanut)." Blockages or splashes are to be avoided. Adaptable speed variation adjustment helps "solve the contradiction between speed and accuracy, and ensure error-free counting (counting error of 0/1000)" Manual feeding vs automatic cup changing "improve the counting efficiency, reduce labor intensity." Automatic discharge can obviate demands for the operator to constantly feed the vibrating plate. One counter is so fast that Millet "counting can reach 2000 grains/min, and the wheat and rice counting" Suitability of the vibrating plate for different seeds is a consideration. It is useful to have an adjustable baffle at the exit of the bowl "according to the diameter of the seeds (workpieces), only one seed (workpiece) at a time, not side by side, for all large and small seeds."[10]

Some seed counters use laser light.[11]

In counting, it is important to position one seed at a time by manipulating slit width when using a Photoelectric seed counter.[12] It can be an integral part of a Seed drill.[citation needed]

Some are able to handle up to 23 sample containers. They can do this while maintaining notable accuracy.[A] General purpose electronic seed counters usually count seeds during free fall. They have achieved satisfactory error rates.[11] For example: "Counting errors of less than 0.4% at counting speeds of 400 to 1,180 seeds/min were obtained for seeds of nine different species ranging in size from corn (Zea mays L.) to trefoil (Lotus corniculatus L.). Under some conditions, the seed dispenser, a vibratory small parts feeder, segregated wheat kernels (Triticum aestivum L.) into weight classes dispensing heavier kernels first into the counting system."[13][14]


See also



  1. ^ "An automatic seed counter for counting seeds from 1–23 sample containers into 1–23 collecting containers is described. The counter can count and collect either a predetermined number of seeds from each sample or the total number of seeds in each sample. Although the instrument was designed for rapeseed, the counter can accommodate seed species ranging in size from 0·6 to 12·5 mm. For large samples (> 100 seeds), the count accuracy varies from ±1% to ±2%, depending on the size and shape of the seed. When counting in the predetermined mode with small samples (<100 seeds) of small seeds, the count accuracy is reduced to ±3%. Accuracy when counting rapeseed is within ±1·16 seeds standard deviation for sample sizes within the range 10–100 seeds, in either predetermined or total count mode. At present this equipment is not suitable for counting seeds from breeder selections because of the possibility of transferring a seed or seeds from one sample to another; minor changes to the control circuit should make this feasible. It is, however, suitable for the majority of counting requirements for a broad range of seeds.[11]


  1. ^ a b "Electronic Counter for Seeds Developed". San Antonio Express. May 24, 1962. Retrieved October 27, 2021.
  2. ^ Arya, Renu; Arya, Sonam; Kumar, Janardhan (February 18, 2020). Fundamentals of Agriculture. Vol. 1. Scientific Publishers. p. 210. ISBN 9789389412796.
  3. ^ a b "The Future for Food Retailing". Agricultural Marketing. United States: Agricultural Marketing Service: 7. 1961.
  4. ^ "Advancements in Seed Counting Technologies Prompt Committee to Pursue Rule Change Proposal". Iowa State University Seed Science Center. Retrieved October 27, 2021.
  5. ^ "Savvy Seed Sorter Gains New Fans, USDA ARS Online Magazine Vol. 61, No. 6". Agricultural Research Service. July 2013. Retrieved October 27, 2021.
  6. ^ "Colorado's Expert Protects Growers Against Poor Seed". The Bismarck Tribune. April 13, 1931. Retrieved October 27, 2021.
  7. ^ "Improvements, Additions Set at Pioneer Research Station". Huron Daily Plainsman. February 25, 1973. Retrieved October 27, 2021.
  8. ^ Carlow, C.A. (June 1968). "Note: An electronic seed counter" (PDF). Journal of Agricultural Engineering Research. 13 (2): 187–189. doi:10.1016/0021-8634(68)90094-2. ISSN 0021-8634 – via Elsevier.
  9. ^ a b c d "Contador Electronic Seed". Pfeuffer (Germany).
  10. ^ "DC-3 Automatic Electronic Seed Counting Machine for Seeds Medical Particles". Gemstone. Retrieved October 30, 2021.
  11. ^ a b c Reid, W.S.; Buckley, D.J. (September 1974). "A laser light source seed counter". Journal of Agricultural Engineering Research. 19 (3): 265–269. doi:10.1016/0021-8634(74)90065-1.
  12. ^ Reid, W.S.; Buckley, D.J.; Mason, W. (June 1976). "A photoelectric seed counting detector". Journal of Agricultural Engineering Research. 21 (2): 213–215. doi:10.1016/0021-8634(76)90077-9 – via ScienceDirect.
  13. ^ Reid, W.S.; Buckley, D.J.; Downey, R.K. (March 1983). "A semi-automatic seed counter". Journal of Agricultural Engineering Research. 28 (2): 89–95. doi:10.1016/0021-8634(83)90078-1 – via ScienceDirect.
  14. ^ McLaughlin, N. B.; Giesbrecht, J.; Bligh, D. F. (April 1976). "Design and Performance of an Electronic Seed Counter". Canadian Journal of Plant Science. 56 (2): 351–355. doi:10.4141/cjps76-053.

External links

  • Dodder counting machine
  • Video of a table top seed counter