J. Am. Soc. Agronomy 16(10): 670-682 (Oct 1924)
Relation of seed size to the yield of small grain crops
Kiesselbach, T.A.

SUMMARY OF NEBRASKA TESTS

Where tests were made with hand selected large and small seed which represented extreme grades of the three cereals, winter wheat, spring wheat, and oats, small seed yielded (1) eighteen percent less than large, when spaced to permit maximum individual plant development, (2) ten percent less when equal numbers of seed were sown per acre at an optimum rate for the large seed, and (3) five percent less when equal weights of seed were sown per acre at an optimum rate for the large seed. When unselected seed was used it yielded (1) four percent less than the large when equal numbers were sown per acre, and (2) one percent less when equal weights of seed were sown.

A comparison of the large with the unselected seed is of the greater importance from the farmer's standpoint.

Comparing fanning mill grades of winter wheat during a seventeen year period, the heaviest one-fourth yielded 0.3 percent more, and the lightest one-fourth two percent less than the unselected.

Kherson oats was separated into the heaviest one-fourth, and the lightest one-fourth and compared with the original unselected seed during eighteen years. The heaviest one-fourth yielded 0.9 percent more, and the lightest one-fourth yielded 0.7 percent less than the unselected.

In general, the work at the Nebraska station indicates that there will be no material or practical gain in the grain yield, under farm conditions, from the practice of grading small grain seed which is reasonably free from trash.

Seed Size, Growth and Yield