Crop Yield Trials
Established in 1988, the Graves-Chapple Farm is a research and demonstration site located in southwest Atchison County and Northwest Holt County adjacent to Interstate Highway 29.
Studies at this site are devoted to various agronomic practices, with a major emphasis on the production of corn and soybeans and some forage work. Varieties for these performance trials are entered by seed companies, which pay an entry fee for each variety. Companies select which trial is planted using a lattice or randomized complete block field plot design with three or four replications.
Corn test plots are four rows 10 feet wide (30" rows) by 25 feet long, except in the narrow row corn study (15 inch rows) with the center rows harvested for yield data. Soybean plots were planted in 15-inch rows by 25 feet long.
The planting season at Graves was optimal for April planted corn but became more difficult in some areas in May and June in most areas, as the fields were became more moist impacting pre-emergence herbicides applied.
Post herbicide programs were needed in most areas because of new weed flushes from increased soil moisture for planted crops. A number of producers needed to replant soybeans in our area because of increased precipitation prior and during their soybean planting.
Throughout the growing season, timely rains coupled with milder than normal June and July nights allowed for increased yield. A typical growing season would have seen even lower corn and soybean yields with our average normal precipitation. Increased summer rains caused most late planted soybeans to yield higher than most average precipitation years. Corn and soybeans matured before the frost and were harvested in most areas prior to any damaging frost.