Grain sorghum was the staple food of the wintering crows. In eastern Harvey County, where sorghum is not an important crop, its consumption began in August, reached a peak in the last part of November, and fell off sharply in December. The grain sorghum crop is vulnerable to damage by crows and it is ripening in the autumn as the crow population is building up. In certain areas and certain years the loss may be important. An exceptional instance was reported to me of crows taking 40 per cent of the crop from a small field of early ripening sorghum near a roost. Most farmers and county agents interviewed thought that the over-all damage was not great. The crop is usually combined and little remains in the fields after October, when the majority of wintering crows arrive. Nevertheless, even waste grain picked up after harvest should be counted as a loss on some farms where stock are turned in to clean up such grain. Oats were taken sparingly as waste grain in summer, autumn, and winter, and most were eaten in late winter and early spring from newly sown fields (37.2 per cent of the February diet and 72.6 per cent of the April diet). These percentages were probably high, since there is a high proportion of indigestible residues in oats. This is more than compensated for in the yearly average by the paucity of collections made in the period when consumption of oats was highest. Fields newly sown to oats provided a major supply of food in the early spring when other food supplies had been depleted. However, no instance of damage to a stand of oats was reported to me. Aldous (1944:294) mentioned that crows fed on spring-sown oat fields in Oklahoma but suggested that they picked up only grain which was not covered. Sunflower seeds, although not important as a food of the crows in eastern Harvey County, were a staple food of these wintering in the western part of the study area. Consumption of sunflower seeds began in September. In the latter part of December the percentage increased and many pellets were composed entirely of sunflower seed hulls. Sunflower seeds have a high percentage of indigestible residue. In both popular accounts and scientific studies, the economic significance of the consumption of weed seeds such as those of sunflowers by birds often has been interpreted in an oversimplified manner. It has been assumed that if crows eat several million sunflower seeds in the winter, the sunflowers growing in the farmers' fields the next year will have been reduced by the same number. However, like most annual plants, sunflowers produce a great surplus of seeds each year. Most of the seeds consumed by crows would never have a chance to grow to maturity, even if they were not eaten. Therefore this component of the crow's diet is only slightly beneficial or neutral for the farmer. The effect of crows (or of the entire bird population for that matter) upon the sunflower crop in the farmers' fields is probably slight.