Most farmers know that inbreeding is injurious both to plants and animals; they could have told these scientists that they were wasting their time - in fact, worse. They were right; production went steadily down. After a few generations of this self-fertilization, many plants were so weak that they died before reaching the tasseling stage. Those that did live were small and feeble. Instead of the large, fat ears that corn should have, only nubbins were harvested.

But these men were interested in something more than yield. They wanted to know why the yields went down, how far they would be reduced, and in what way the inbred plants would differ from naturally pollinated plants. Then, too, what would happen when these inbred plants were crossed with each other? They tried crossing and were themselves astonished at the vigorous growth and increased productiveness of the intercrossed plants the very next year after crossing. They noticed, also, that the crossed plants of any one combination of inbred parents were closely alike; each plant grew to the same height, silks and tassels appeared at the same time, and every plant, when rightly grown, had good ears on every stalk. A row of this hybrid corn looked like a line of West Point cadets on parade. The uniformity was an indication of the high production from every plant, a very important factor in the extraordinary high yields that have since been obtained from this crossed seed.

This was the kind of seed that Wallace offered to compare in productive value with the best that the corn farmers had been able to produce. His inbred strains were collected from several places; some he had produced himself. They had all been tested in various combinations. The nubbins that he pictured on the front page of his magazine had been grown on inbred plants and were consequently poor, but in each kernel there was a hybrid union of different heredities, purified by inbreeding. Each by itself was weak, but in combination, powerful.

In every district in Iowa - the United States Department of Agriculture has made careful yield tests - this crossed corn has given more bushels of good sound grain than the best of the varieties previously grown. Similar reports are coming from other states. Canners and market gardeners are finding that the same method applied to sweet corn gives astonishing results. The evenness in size and shape of ear and the ability to ripen at the same time are of even greater importance for sweet corn than for field corn.

Seed growers are taking an active interest in this new method, and fields used for the production of crossed corn seed are being planted with the two inbred types to be crossed in alternating rows. In midsummer, as soon as the tassels appear and before any pollen is shed, crews of tassel pullers go into the field and jerk out the opening panicle at the top of the plant from those rows that are to supply the seed. The ears on these detasseled plants receive their pollen from the adjacent rows, planted solely for the purpose of supplying pollen. This crossed seed is used only once. Later generations fall off in vigor and yield. The extra vigor and production in the first hybrid generation more than pay for the additional expense of producing seed in this new way.

In all the years that he has been growing plants and feeding farm animals, the farmer, faced with the necessity of making a living from the soil, has never carried his few random observations on inbreeding beyond the point where production was first affected. By going farther, patient investigation, supported by the methods of science, has discovered a new way to better yields. The corn grower has known all along that the best ears saved for seed would invariably produce many nubbins. Science now shows how a bumper crop of all good ears can be grown from nubbins. But they must be the right kind of nubbins.