Heavier seed stays on the deck and moves to the high end of the table while lighter seed rises to the top and falls to the lower end Since seed flows over the deck, internal machinery damage to the seed is nominal. Germination enhancing chemical treatments are not used with our grading procedure. This means there is no concern with drop in germination or limited shelf life. Density grading deals with the weight of the seed, not the size, therefore, belt changing is not required. Density grading has shown improvements in plant population and quicker emergence while reducing costs in both direct seeding and greenhouse transplanting environments.
Density grading seed is an effective, low risk, minimal loss process.
Density grading can be used as an effective substitute to priming for some types of seed, but Pacific Grading Service suggests using density grading in addition to priming to insure optimum uniform emergence.