Conservation alternatives that include no-tillage (NT) and cover crops (CCs) reduce soil erosion in row-crop agroecosystems. However, little information is available about how these alternatives affect soil textural properties responsible for soil fertility. This study evaluated the soil particle size distribution and volumetric water content after three years of consistent management in a raised bed system. There were four treatment systems in a dryland maize/soybean rotation on a silt loam soil (Oxyaquic Fraglossudalfs) that included: NT + CCs, conventional tillage (CT) + CCs, CT + winter weeds, and CT + bare soil in winter in northwest Mississippi. The NT + CC system retained 62% more coarse sand in the furrow than the other systems (2.1% compared to 1.3%; p = 0.02). Regardless of the location, the NT + CC system (2.5%) retained 39% more fine sand than the CT + CC system (1.8%; p = 0.01), suggesting that coarse and fine sands were being trapped in furrows combining NT + CC systems, minimizing their off-site transport. In furrows, CCs increased soil volumetric water content by 47% compared to other winter covers. In beds, NT + CCs increased bed water contents by 20% compared to CT + CCs (17.1 to 14.3%; p < 0.01). Implementing conservation alternatives may promote the retention of sand fractions in silty loam soils that are important in supporting soil fertility and crop sustainability.

The abundance and distribution of soil microbial populations, i.e., microbial diversity is widely promoted as a key tenant of sustainable agricultural practices and/or soil health. A common approach to describing microbial diversity is phylogenetic analysis with high-throughput sequencing of microbial DNA. However, owing to the tremendous amounts of data generated, a continuing effort is required to better assess the effects of agricultural management systems on soil microbial diversity. Here, we report on the combined effects of management systems on bacterial and fungal diversity in a loessal agricultural soil located in north-central Mississippi, USA. Amplicon sequencing was performed using 16S rRNA-gene and ITS2 from soil samples collected from a three-year study with combinations of maize-soybean crop rotation, tillage practices, and winter vegetative covers. Differences were found in microbial fungal β-diversity among the management systems, with distinct clustering patterns for no-tillage combined with either winter weeds or bare-fallow. Management systems showed a significant influence on soil pH and bulk density, which were positively correlated with fungal community composition. Developments in the description and interpretation of soil microbial diversity will contribute to a more accurate understanding of its role in the various functions and processes important to agricultural soil management.

Accelerometer-based technologies can be used for precision monitoring of feeding behaviors, but limited information is available regarding the effect of varying environmental conditions on sensor performance. The objective of this study was to determine if a commercially available ear-tag sensor (CM; CowManager SensOor, Agis Automatisering BV) could accurately quantify eating and rumination time under heat stress conditions. Data obtained from CM sensors was compared with data collected using an automated gold standard (RW; Rumiwatch System; Itin+Hoch). Automated measurements were obtained from 2 experiments in which cattle were exposed to heat stress conditions. In the principal study (experiment 1), 3,428 h of data were collected from 9 Holstein × Angus steers (470.9 ± 23.9 kg) subjected to either thermoneutral (TN; 21.0°C; 64.0% humidity; temperature-humidity index [THI] = 67; 12- and 12-h light and dark cycle; n = 1,714 h), or heat stress (HS) conditions (cyclical daily temperatures to mimic diurnal patterns; 0800-2000 h: 33.6°C, 40.0% relative humidity (RH), THI: 83.5; 2000-0800 h: 23.2°C, 70.0% RH; THI: 70.3; n = 1,714 h). Data (n = 719 h) from 6 Holstein × Angus steers (487.9 ± 9.1 kg) were obtained from a subsequent experiment (experiment 2) to confirm consistency of ear-tag accelerometer performance under elevated THI (HS conditions as described above). In experiment 1, CM was capable of quantifying rumination time with high accuracy under TN conditions (concordance correlation coefficient [CCC]: 0.75-0.81). Overall, agreement between CM and the automated gold standard declined 6% to 7% during HS, which was most apparent later in the day when cattle had been subjected to HS for multiple hours (moderate agreement; CCC: 0.68). Accuracy for rumination time was also only moderate for data collected during experiment 2 (CCC: 0.55-0.61). In contrast, CM reported total eating (eating with the head down + head up while masticating) time with moderate accuracy for TN (CCC: 0.53-0.54), only achieved negligible to low accuracy during HS (CCC: 0.39-0.44 [experiment 1] and 0.17-0.34 [experiment 2]). Sensor performance did improve when CM eating time was compared specifically to the time spent with the head down reported by RW; HS still negatively influenced sensor performance, however, with high agreement during TN (CCC: 0.72-0.73) but low to moderate agreement during HS (CCC: 0.65-0.69 [experiment 1] and 0.40-0.58 [experiment 2]). Results of this study suggest accuracy of ear-tag accelerometers may be impaired when cattle are subjected to heat stress.

Nitrogen (N) requirements for switchgrass (Panicum virgatum L.) forage production in the Mid‐south are largely unknown. This study determined switchgrass forage yield, quality, N removal, and soil fertility response in a two‐forage harvest (pre‐anthesis) system after split applications of 0, 84, 168, 252, and 336 kg N ha^–1 yr^–1 from 2014 to 2016. Controls were represented by no fertilizer and a 0 N rate with supplemental P, K, Mg, and S. For all experimental years, yield did not benefit from supplemental P, K, Mg, and S, suggesting N was the limiting nutrient. Yield also did not differ between the 252 and the 336 kg N ha^–1 yr^–1 rates (9.2 and 9.4 Mg ha^–1, respectively), indicating no further growth beyond the 252 kg N ha^–1 threshold in a two‐cut forage system. At greater N fertility rates (336 kg N ha^–1), the majority of the soil nutrient concentrations were reduced compared with the 252 kg N ha^–1 rate, owing to greater nutrient removal in harvested plant tissue. Tissue N removal was greatest for the highest N application, albeit not different from the 252 kg N ha^–1 rate; N use efficiency had an inverse relationship with N removal, peaking during the lowest N application (84 kg N ha^–1). Forage quality varied, but, in general, digestibility improved under greater N fertility. Quantifying trends in forage yield and quality based on N fertility are useful for predicting break‐even prices per fertilizer response.