Nitrogen (N) management is a critical agronomic challenge, as N losses are source of pollution affecting both waterways and air quality potential economic loss for farmers. One approach to conservation through ecologically based agricultural systems that reduce tillage incorporate cover crops. However, these exhibit considerable complexity resulting in trade-offs. To address concerns, four crop...

Time, fertilizer, tillage, and cropping systems may alter soil organic carbon (SOC) levels. Our objective was to determine the effect of long-term cropping systems and fertility treatments on SOC. Five rotations and two N fertility levels at three Iowa sites (Kanawha, Nashua, and Sutherland) maintained for 12 to 36 yr were evaluated. A 75-yr continuous corn (Zea mays L.) site (Ames) with a 40-y...

• Tillage intensity increased soil organic C losses and risks of wind water erosion. Occluded POM was more management-sensitive in smaller than larger sized aggregates. Maximizing plant inputs via cropping system type partially mitigated negative tillage effects. Soil disturbance from N management limited mitigating effects system. increases the susceptibility agricultural soils to erosion carb...

The aim of this study was to evaluate the response corn (Zea mays L.) grain yield nitrogen (N) fertilizer application and its residual effect on soybean (Glycine max (L.) Merr.) seed yield. During 2020 growing season, a corn-soybean rotation continued at Scandia, KS (USA), evaluating five N rates in under both dryland irrigated conditions. Average yields ranged from 110 206 bu/a for dryland, 19...

Long-term applications of organic or inorganic sources of N to croplands can increase the leaching potential of nitrate– nitrogen (NO3–N) for soils underlain by subsurface drainage ‘‘tile’’ network. A field study was conducted for 6 years (1993– 1998) to determine the effects of liquid swine manure and urea ammonium nitrate (UAN) solution fertilizer applications on NO3–N concentrations and NO3–...

BACKGROUND Interest in the cultivation of biomass crops like the C4 grass Miscanthus x giganteus (Miscanthus) is increasing as global demand for biofuel grows. In the US, Miscanthus is promoted as a crop well-suited to the Corn Belt where it could be cultivated on marginal land interposed with maize and soybean. Interactions (direct and indirect) of Miscanthus, maize, and the major Corn Belt pe...

Dual-use cover crops as forage for livestock could offer ecological and economic benefits when incorporated into rotations with corn (Zea mays L.) soybean (Glycine max (L.) Merr) in the Mid-South USA; however, information on implementation impact is limited. A factorial of sixteen cool-season species a no-cover control by two management systems (forage harvest residue left field) was repeated u...

Optimum plant stand density and uniformity is vital in order to maximize corn (Zea mays L.) yield potential. Assessment of can occur shortly after seedlings begin emerge, allowing for timely replant decisions. The conventional methods evaluating an early rely on manual measurement visual observation, which are time consuming, subjective because the small sampling areas used, unable capture fiel...

Perennial grasses are the backbone of the U.S. livestock industry and are widely recognized as a key in conserving soil. Certain government programs require perennial grasses such as the Conservation Reserve Program (CRP) as a way to enhance and protect soil quality while setting aside land from production. Perennial grasses are used along roadsides all across the country to provide stable slop...