Choice of Summer Fallow Replacement Crops Impacts Subsequent Winter Wheat

Abstract

Winter wheat (Triticum aestivum L.) is the foundation of dryland cropping systems in the Central Great Plains. The objective of this study was to quantify the effects of four short‐season spring‐planted crops used to replace summer fallow on the subsequent winter wheat crop. Wheat was seeded into four crop stubbles [spring triticale (×Triticosecale Wittmack), dry pea (Pisum sativum L.), foxtail millet (Setaria italica L. Beauv.), and proso millet (Panicum miliaceum L.)] at sites near Akron, CO, and Sidney, NE, in the fall of 2004 and 2005. These summer fallow replacement crops were planted into silt loam soils at three different soil water levels at planting (low, medium, and high). Winter wheat water use was 3.6 cm greater, and grain yield was 662 kg ha−1 greater in the high water treatment compared with the low water treatment averaged across all sites and years. Winter wheat used an average of 4.3 cm more water following early planted summer crops (triticale and dry pea) than after late planted summer crops (foxtail and proso millet), but this increased water use did not consistently translate into increased grain yield as a result of terminal drought at Sidney in 2006. The high water treatment always had a positive net return. The high cost of pea seed ($3.30 kg−1, USD) strongly reduced profitability. The flexible summer fallow cropping system appears to be most applicable when using short‐duration summer annual forage crops such as triticale and foxtail millet.

Searching for synergism in dryland cropping systems in the central Great Plains

“…Soil water content at planting has a strong influence on crop yield Nielsen and Vigil, 2005;Felter et al, 2006, Lyon et al, 2007Nielsen et al, 2008). Therefore, data from the first five years of the study (1991)(1992)(1993)(1994)(1995) are not considered in the analysis presented in the paper (1996-2011) as we considered those years to be the time period in which the rotations were being established and from which time forward the true effects of the rotational sequences, primarily due to differences in soil water content, could be evaluated.…”

“…They did not report consistent effects of previous crop type on WUE of spring wheat, but WUE was generally lower when wheat was preceded by a crop than when wheat was preceded by a fallow period. Lyon et al (2007) reported results from a 2-year study conducted at two central Great Plains locations (Nebraska Panhandle, northeastern Colorado) in which the effects of preceding crop (triticale [X Triticosecale Wittmack], pea, foxtail millet [Setaria italica L. Beauv.…”

Replacing Fallow with Cover Crops in a Semiarid Soil: Effects on Soil Properties

“…Our results cannot be directly compared with other studies as there is limited information on CC effects on soil properties in the central Great Plains under no-till conditions. Most previous studies in this region focused on water use and grain yields in CCs used as green manure under conventional till (Schlegel and Havlin, 1997;Nielsen and Vigil, 2005;Felter et al, 2006;Lyon et al, 2007).…”

Prediction of Plant Available Water at Sowing for Winter Wheat in the Southern Great Plains

“…Th e simulations by Zhang (2003) were performed in a region where the 28-yr growing season precipitation average was ~485 mm, suggesting that PAW s may be a stronger limiting factor to wheat grain yields in the western portion of the Great Plains, region characterized by lower growing season precipitation. Indeed, Lyon et al (2007), Norwood (2000), and Stone and Schlegel (2006) found reduced wheat yields associated with reduced PAW s in Colorado and western Kansas, highlighting the positive linear relationship between PAW s and rainfed wheat yields in wheat-fallow systems in the Great Plains.…”