South Dakota Corn Performance Tests, 1958

Yield trials on those corn hybrids currently most popular among farmers are conducted each year by the Agronomy Department of the South Dakota Agricultural Experiment Station. The purpose is to supply farmers and ranchers with information on the relative performance ability of the various hybrids when they are subjected to similar environmental conditions such as rainfall, soil moisture, and fertility level. Such information, when used as a guide in selecting hybrids for planting, can aid the farmer in obtaining maximum yields under his field conditions. In 1958, 14 tests were planted throughout South Dakota. Each contained from 20 to 40 entries planted in replicated plots. Yields, moisture percentages at harvest, and in some cases lodging, were obtained and are presented in the tables in this publication. All areas east of the Missouri River received below normal rainfall with the extreme deficiency occurring in the southeast corner. The recorded rainfall for the test location in area 8B was 8.56 inches for the period May 1 through September 30. This amount was half of the normal for the location. Less deviation from normal was found north and west of this area. The below normal deviations were greatest in all areas during July and August. Average departure from normal temperature for the May-September period were all below normal except in areas 8B and 2. At these locations close to average temperatures were reached. These averages do not reflect the extreme below normal temperatures received over the entire state during July. Hail eliminated one test and seriously reduced the yields of another at the Newell station. This station received two hail storms - June 7 and July 10. The irrigated plot was harvested for yield but the dryland failed to produce reliable data. Killing frost occurred at all locations near or later than normal dates. There were some entries that even with the normal fall frost date did not produce mature, good quality corn. In general, the earlier varieties yielded better, which was probably due to the increasing stress from the lack of moisture towards the end of the growing season. Drying conditions in the fall were excellent and except for the varieties too late for the given area the quality of the crop was good. Yields were found to be below five year averages for all areas east of the Missouri River. This undoubtedly was a reflection of the lack of moisture during the growing season