EC33-136 Corn in Nebraska

Corn is Nebraska's most important crop. Of the nearly 19 million acres under cultivation in the state, over 10 million acres or more than 50 percent is normally planted to corn. This is three times the acreage of wheat, four times that of oats, and ten times that of barley. The 10-year average acre yield of corn for this state is 25.8 bushels compared with 26.9 bushels for the entire United States. Nebraska, with an average annual crop of approximately 258 million bushels, usually ranks third among all states in the total production of corn, being exceeded by Iowa and Illinois. This 1933 extension circular discusses the importance of corn, seed, varieties of corn, freezing injury, testing seed corn, hybrid corn, soil fertility and rotation, cultural practices, harvesting and storing corn, power machinery in relation to costs in corn production, corn diseases and insects, and utilization of corn.

SAMPLING OF CORN TO ASSESS BIRD DAMAGE: A Preliminary Review of a Comprehensive Study

"How large a sample is needed to survey the bird damage to corn in a county in Ohio or New Jersey or South Dakota?" Like those in the Bureau of Sport Fisheries and Wildlife and the U.S.D.A. who have been faced with a question of this sort we found only meager information on which to base an answer, whether the problem related to a county in Ohio or to one in New Jersey, or elsewhere. Many sampling methods and rates of sampling did yield reliable estimates but the judgment was often intuitive or based on the reasonableness of the resulting data. Later, when planning the next study or survey, little additional information was available on whether 40 samples of 5 ears each or 5 samples of 200 ears should be examined, i.e., examination of a large number of small samples or a small number of large samples. What information is needed to make a reliable decision? Those of us involved with the Agricultural Experiment Station regional project concerned with the problems of bird damage to crops, known as NE-49, thought we might supply an ans¬wer if we had a corn field in which all the damage was measured. If all the damage were known, we could then sample this field in various ways and see how the estimates from these samplings compared to the actual damage and pin-point the best and most accurate sampling procedure. Eventually the investigators in four states became involved in this work1 and instead of one field we were able to broaden the geographical base by examining all the corn ears in 2 half-acre sections of fields in each state, 8 sections in all. When the corn had matured well past the dough stage, damage on each corn ear was assessed, without removing the ear from the stalk, by visually estimating the percent of the kernel surface which had been destroyed and rating it in one of 5 damage categories. Measurements (by row-centimeters) of the rows of kernels pecked by birds also were made on selected ears representing all categories and all parts of each field section. These measurements provided conversion factors that, when fed into a computer, were applied to the more than 72,000 visually assessed ears. The machine now had in its memory and could supply on demand a map showing each ear, its location and the intensity of the damage.