The eastern panhandle region of West Virginia is entirely within the Appalachian Ridge and Valley ecoregion. It is underlain by limestone in the eastern part and by shale and sandstone in the western part. Agricultural and urban development has affected the condition of the streams of this region. We examined samples from 165 stations in the Ridge and Valley, collected from 1998 to 2004. Land use, geological characteristics, physical and chemical parameters, and algal and macroinvertebrate assemblages were used to identify potential stressors that affect streams in the region. Our analyses indicated that both human land uses and ecoregional differences led to elevated nutrient concentrations in streams of the study areas. Multiple regression analyses indicated that both agricultural and urban land use in the watershed were associated with high nutrient concentrations (NO2+3, total nitrogen, and total phosphorus) in streams. These elevated nutrient concentrations have led to increased algal biomass, increased trophic state, and degradation of macroinvertebrate community in the streams. Values of the West Virginia Stream Condition Index, as well as several other benthic macroinvertebrate metrics, decreased with increased nutrient concentrations and conductivity, especially in the limestone region. When regional differences were partitioned out in the analysis, nutrient concentrations became the strongest stressor in the limestone region while conductivity exhibited less of an effect on macroinvertebrate metrics. Meanwhile, periphyton diagnostic metrics also responded to increased nutrient concentrations, suggesting nutrients could be a cause of biological degradation in the Eastern Ridge and Valley region. Multiple approaches and multiple lines of evidence (reference approach and stressor‐response approach) were applied to develop nutrient benchmarks for different geological regions in the study watershed.

Stalk lodging in corn (Zea mays L.) leads to harvest complications and yield losses. Farmers who apply a foliar fungicide to manage leaf diseases have also observed reduced lodging. The goal of this study was to evaluate the effect of a foliar fungicide applied at silking on percent lodging. Field trials were established on Iowa State University Research Farms in 2016 and 2017. Treatments evaluated were foliar fungicide application (with or without) and harvest date (corn harvested at weekly intervals for up to 5 weeks); a split plot design was used with four complete blocks. Across all locations and years, a fungicide application significantly reduced mean lodging (P < 0.0001) by 9.3% and increased yields (P = 0.0043) by an average of 258.3 kg/ha (4.1 bu/acre). Percent lodging increased as harvest was delayed (P < 0.0001). This study demonstrated that foliar fungicides applied at silking reduced lodging and thus confirmed observations of farmers. Applying a fungicide to reduce lodging and favor harvest, however, is not recommended due to risk of fungicide resistance development and the lack of efficacy on stalk rot pathogens.

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