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Soil texture and organic matter are considered overarching factors controlling a diversity of soil processes and properties. However, a more complete understanding of how these factors quantitatively affect other soil properties has been lacking due to either limited scope of land use and management conditions, confounding climate and environmental conditions with management, or narrow range of soil and management conditions. This study evaluated the strength of associations of sand and total soil N concentrations with soil physical, chemical, and biological properties and processes from 310 surface‐soil (0–10‐cm depth) samples (87% Ultisols, 4% Inceptisols, and ≤3% each of Alfisols, Spodosols, Entisols, and Histosols) collected under conventional‐till and no‐till cropland, grassland, and woodland in four physiographic regions of North Carolina. Sand concentration was most strongly associated with dry‐stable mean‐weight diameter (MWD), MWD product, and sieved soil density (|r| > 0.63, p < 0.001). Total soil N concentration was most strongly associated with particulate organic C and N and soil water content at water‐holding capacity (|r| > 0.74, p < 0.001). Soils under unfertilized woodlands deviated the most from general associations, suggesting that organic matter quality could be unique, and requires further investigation. Overall, sand concentration associated more closely with soil physical properties and total soil N concentration associated closely with both soil physical and biogeochemical properties. Soil chemical properties were only weakly associated with either property. This study suggests that soil texture and organic matter would be complementary, additional properties in holistic soil health assessments that already included routine soil chemical analyses. Core Ideas: Soil texture strongly associated with dry‐stable aggregation but weakly associated with water‐stable aggregation.Total soil N strongly associated with particulate organic C and N and soil water content at water‐holding capacity.Sand and total soil N concentrations were strong combined indicators of bulk density, sieved soil density, and cation‐exchange capacity.Sand and total soil N concentrations were unique soil health indicators in addition to routine soil chemical propertiesSieved soil density could be a relatively rapid and inexpensive indicator that combines the influences of soil texture and organic matter. [ABSTRACT FROM AUTHOR]

Background: Soil organic C and N data from privately managed pastures in the southeastern United States are relatively scant. Methods: A paired‐farm approach was deployed to determine how a variety of soil health parameters related to nutrient and water cycling might be altered under grazed, botanically diverse perennial pastures compared with annual monoculture croplands in three Major Land Resource Areas of the southeastern United States. Results: Soil stability index averaged 0.64 and 0.91 mm mm−1 under cropland and grazed pasture, respectively, suggesting that pastures had a more stable soil surface that was resistant to erosion and allowed rapid water infiltration. Surface‐soil organic C and N fractions (i.e., total, particulate, and mineralizable fractions at 0–10 cm depth) were greater under pasture than under cropland. Across locations, root‐zone enrichments (0–30 cm depth) of organic C and N fractions were greater under pasture than under cropland. Within locations, root‐zone enrichment of total soil N was greater (p < 0.05) under pasture than under cropland in the Blue Ridge (2.87 vs. 1.10 Mg N ha−1, respectively) and the Piedmont (2.80 vs. 2.10 Mg N ha−1), but not in the Blackland Prairie (2.40 vs. 2.12 Mg N ha−1). Conclusions: This study provides evidence that rotationally grazed, perennial grasslands can store more soil organic C and N and improve soil surface stability conditions compared with neighboring croplands producing commodity feed grains for feedlot finishing. [ABSTRACT FROM AUTHOR]

Biologically active and intermediately labile fractions of soil organic matter are important features of conservation agricultural management systems. Depth distribution of soil‐test biological activity (STBA) and particulate organic carbon (C) and nitrogen (N) were characterized under cropland, grassland, and woodland across 25 research stations in North Carolina. Most (87%) of the 310 fields sampled were on Ultisols (udults or aquults). Variation in STBA in the surface 30‐cm of soil was controlled primarily by land use and to a lesser extent by soil texture and physiographic region. Baseline concentrations of STBA and particulate organic C and N at 30‐cm depth were relatively narrowly constrained compared with contents in the 0‐ to 10‐cm depth. Root‐zone enrichment (i.e., total minus baseline contents) of STBA (mean ± standard error; kg CO2–C ha−1 3 d−1) followed the order: conventional‐till cropland (194 ± 17) < no‐till cropland (274 ± 26) < woodland (421 ± 17) < grassland (537 ± 15) across locations. Proportion of root‐zone enrichment of soil organic C as particulate organic C was 43 ± 2%. Root‐zone enrichment of particulate organic C (Mg C ha−1) followed the order: conventional‐till cropland (3.8 ± 0.6) < no‐till cropland (8.7 ± 0.8) < grassland (14.1 ± 0.5) < woodland (16.3 ± 0.6) across locations. The C:N ratio of root‐zone‐enriched particulate organic matter was greater under woodland than under other land uses likely because of N input limitations. Conservation land uses increased root‐zone enrichment of these active and intermediately labile fractions independent of soil types and regions in the state. Core Ideas: Root‐zone enrichment calculations were sensitive to conservation land uses.As a proportion of total root‐zone enrichment of soil‐test biological activity (STBA), 68 ± 7% occurred in the 0‐ to 10‐cm depth.Grasslands and woodlands had greater root‐zone enrichment of particulate organic C and N than croplands.No‐till cropland had greater root‐zone enrichment of STBA and particulate organic C and N than conventional‐till cropland.Greater C:N ratio of root‐zone‐enriched particulate organic matter under woodlands may have been from lack of N input. [ABSTRACT FROM AUTHOR]

Soil aggregation is considered a key indicator of soil health to protect soil against erosion, enhance organic C storage, and offer habitat for soil organisms. Various methods to assess aggregation may change interpretations of management, and therefore should be cross‐calibrated. We assessed the impact of initial sieve opening size (8 or 4.75 mm) prior to determination of dry‐stable and water‐stable mean‐weight diameter (MWD) from two fine‐textured soils—a Rhodic Hapludox from São Paulo, Brazil and a Rhodic Kanhapludult from North Carolina, United States. Both soils were subjected to management expected to alter surface soil conditions. As expected, initial sieving through 8 mm led to greater dry‐stable MWD (3.37 ± 0.60 mm) than initial sieving through 4.75 mm (1.94 ± 0.28 mm). However, soil stability index (water‐stable MWD/dry‐stable MWD) was not affected by initial sieve size opening (0.56 ± 0.13 mm mm−1 under both initial sieve openings). Management interpretations were consistent with both approaches as well, and in particular to detect the strong depth effect on water‐stable MWD (i.e., declining with depth). Water‐stable macroaggregates had 32% ± 25% greater C concentration than microaggregates; similarly under both initial sieving conditions. Soil stability index when initially sieved through 4.75 mm was highly associated with aggregate stability of 1–2‐mm sized dry aggregates, which is a more common procedure. We conclude that passing soil through a screen with 4.75‐mm openings to conduct a diversity of soil analyses can be appropriate for obtaining reasonable estimates of and interpretations about surface soil aggregation. Core Ideas: Soil stability index is water‐stable divided by dry‐stable mean‐weight diameter of whole soil.Soil stability index was similar whether soil was initially sieved through 8 or 4.75 mm.Water‐stable mean‐weight diameter and soil stability index declined with soil depth.Water‐stable macroaggregates had 32% ± 25% greater soil organic C than microaggregates. [ABSTRACT FROM AUTHOR]

Agriculture has undergone dramatic technological and cultural changes over the past century. Many would argue that the changes have been unquestionably positive with huge gains in productivity, reduced labour requirements, and alleviation of food insecurity for most people. However, the adoption of increasingly specialized and separated crop and livestock enterprises has also had widespread negative consequences resulting in (a) decline in biodiversity, (b) degradation of groundwater and surface waters with agrochemical pollutants, (c) poor soil health with monoculture crop production and frequent soil disturbance, (d) intensive greenhouse gas emissions from both specialized cropping systems relying on external inputs and concentrated animal feeding operations that accumulate wastes, and (e) general lack of ecological integrity among components of these specialized systems. Diversified agricultural systems using annual and perennial forages offer opportunities to elevate ecological synergies when crop and livestock operations are integrated. Integrated crop‐livestock systems can internalize nutrient cycling, provide cultural control of weeds, insects and diseases, and share resources in a circular‐based agroecosystem. Cover crops could be transitioned into nutritious annual forages for livestock grazing on currently specialized crop production farms with appropriate local incentives. Perennial forages in ley farming or in pasture‐crop rotations have historical relevance and are a proven practice for conserving nutrients, improving soil health and enhancing biodiversity. Redesigning contemporary agriculture with mixed‐use farming techniques could greatly reduce soil erosion, improve water quality, and invigorate soil health. We suggest that incorporating different types of forages across a diverse landscape can enhance agricultural sustainability and ecological integrity. [ABSTRACT FROM AUTHOR]

Soil erosion is a major constraint to agricultural sustainability. Land management that protects soil from water erosion can be assessed from the fraction of aggregates stable upon water immersion. Conservation management with minimal soil disturbance is known to enhance water‐stable aggregation, but how annual vs. perennial vegetative cover affects soil biological activity and aggregation from soils varying in texture remains relatively unexplored. This study assessed the effects of long‐term conventional‐till and no‐till cropland, grassland, and woodland on dry‐stable and water‐stable mean‐weight diameter (MWD) from 25 research stations across North Carolina. Soil clay concentration varied from 36 to 279 g kg–1 and sand concentration varied from 392 to 904 g kg–1 (5–95% distribution). Across locations, water‐stable MWD followed the order: conventional‐till cropland (0.64 mm) < no‐till cropland (0.87 mm) < woodland (1.12 mm) = grassland (1.15 mm). Soil stability index (i.e., water‐stable MWD/dry‐stable MWD) followed a similar order: conventional‐till cropland (0.59 mm mm–1) < no‐till cropland (0.76 mm mm–1) < grassland (0.92 mm mm–1) = woodland (0.96 mm mm–1). Although water‐stable MWD was positively associated with clay concentration (r =.50, p <.001, n = 310), soil‐test biological activity had the strongest association with water‐stable MWD (r =.80). Soil‐test biological activity reflected biological manipulation of surface‐concentrated organic matter, as mediated by conservation land uses. This study revealed the large impact of surface organic C and N resources on water‐stable aggregation through soil biological manipulations interacting across a textural gradient. Core Ideas: Conservation land uses of no‐till cropland, grassland, and woodland improved soil aggregation characteristics.Soil stability index discerned conservation land use impacts across a soil texture gradient.Soil aggregation characteristics were not different between grasslands and woodlands.Soil‐test biological activity and sand were strongly associated with soil aggregation characteristics. [ABSTRACT FROM AUTHOR]

Estimating soil nitrogen (N) availability is important for developing effective N fertilizer recommendations for plant growth. We examined the ability of various soil biological properties to predict soil N availability, and plant dry matter and N uptake in two greenhouse trials with sorghum-sudangrass (Sorghum bicolor (L.) Moench ssp. Drummondii) as test crop using soils (0–10 cm) from 57 tall fescue (Schedonorus arundinaceus (Schreb.) Dumort.) pastures mostly in North Carolina and Virginia. Soil biological properties, the flush of CO2, cumulative carbon (C) mineralization, soil microbial biomass C, basal soil respiration, and plant available N were positively correlated with net N mineralization, plant dry matter, and N uptake in both the greenhouse trials. The flush of CO2, which is the measure of carbon dioxide released from dried and rewetted soil during the first 3 days of aerobic incubation, explained 77% and 72% of the variation in the plant N uptake in Greenhouse Trial 1 and 2, respectively. Total soil N and residual inorganic N in both trials and manganese in Trial 1 and particulate organic C in Trial 2 added minor contributions to explaining variation in plant N uptake. The flush of CO2 was reflective of management history and soil texture. We conclude that the flush of CO2 is a reliable predictor of soil N availability across diverse pasture soils because (a) it was highly correlated with net N mineralization, plant dry matter, and N uptake, and (b) it was less laborious and more cost-effective than other direct indicators of soil N availability. [ABSTRACT FROM AUTHOR]

The cover image is based on the Original Article Farming with forages can reconnect crop and livestock operations to enhance circularity and foster ecosystem services by Alan J. Franzluebbers et al., https://doi.org/10.1111/gfs.12592. [ABSTRACT FROM AUTHOR]

Lack of forage in the winter dry season is a concern for cattle production in tropical Brazil. Pasture renovation with silage production might solve an immediate concern for forage production and help develop an improved pasture condition after cropping. The present study was focused to compare the production and quality of monocropped sorghum and sorghum intercropped with Marandu grass and/or pigeonpea in two row spacings. The experiment was carried out on a sandy Oxisol in São Paulo state in Brazil with an experimental design of a 2 x 4 factorial arrangement with four replications. Treatments were: monocropped sorghum, sorghum intercropped with Urochloa brizantha, sorghum intercropped with Cajanus cajan (cv. BRS Mandarim), and sorghum intercropped with Urochloa+ pigeonpea with 0.45 and 0.90 m row spacings. Greatest forage production was with 0.45-m spacing for monocropped sorghum and dual-species intercropping. With 0.90-m spacing, greatest production was for Sorghum+Urochloa. Sorghum+Urochloa+Cajanus intercropping provided the highest concentrations of crude protein in silage, regardless of row spacing. An increase in ensiling time reduced quality of the silage due to a decline in crude protein and TDN and an increase in fibers. However, the reduced spacing between lines with the inclusion of legumes resulted in a greater amount of silage with a higher concentration of protein. [ABSTRACT FROM AUTHOR]

Sustainability research is complex and involves the evaluation of tradeoffs. Environmental, economic, and social aspects should ideally be considered. Even when one only pillar of sustainability is evaluated, results should be assessed within the broader context of overall sustainability. Environmental impacts from forage and livestock systems, as well as confined animal feeding operations, can be positive and negative, depending on the type of operation, environmental setting, weather episodes, and management conditions. These systems also have associated social and economic impacts. As in all agricultural management systems, there are likely to be hotspots of damage due to a particular management style combined with the right soil, landscape, and climatic conditions. Widespread, positive benefits of pasture-based management are possible when forage resources are utilized ideally with best grazing management principles leading to enhanced soil organic carbon storage, high water infiltration, efficient nutrient cycling, and minimal water and nutrient runoff into nearby water bodies. Research to quantify the environmental impacts of livestock management systems can be designed in detail on research stations to understand the direct implications of management differences on plant biomass production that captures atmospheric CO2, on carbon stored in soil organic matter, and on greenhouse gas emissions from ruminant livestock fed controlled diets. On-farm research is also valuable to characterize the impacts of a particular style of management across a diversity of environments using a system-level approach integrated across the farm. Communication strategies engaging major stakeholders from the livestock industry are key to deliver a consistent message to the general public. Perceived benefits, challenges, and opportunities must be science based, seeking opportunities to reduce negative impacts, and enhancing the positive ones. Messaging to the lay audience about environmental impacts can be focused on solutions from positive benefits or problems from negative effects, but should also address economic and social components. [ABSTRACT FROM AUTHOR]

The objective of this study was to analyze animal performance following renovation of toxic-infected tall fescue (TF) to novel endophyte tall fescue (NE) in order to increase producer adoption of NE. In 2018, three renovation strategies were implemented in a randomized complete block design. Strategies included: 1) control (C), 2) renovation to NE after one season of a single-specie cover crop (1-SM), 3) renovation to NE after three seasons of a single-specie cover crop (3-SM), and 4) renovation to NE after three seasons of a multi-specie cover crop (3-CM). Forty-eight pregnant (30-90-d) Angus heifers (initial BW 383 kg ± 32) were randomly assigned to rotationally graze spring growth for 56-d, two years after NE establishment. Pre- and post-grazing forage mass was measured every 7-d. Animal measurements were collected every 14-d. Data were analyzed using procGLIMMIX of SASv9.4. Average daily gain was greatest (P < 0.0001) for cattle grazing 3-CM (0.74 kg/d), 1-SM (0.72 kg/d), and 3-SM (0.62 kg/d) and least for C (0.33 kg/d). Pre-grazing forage biomass was greatest (P = 0.0157) in 3-CM (3261 kg/ha) and lowest in C (2523 kg/ha), with 3-SM (2813 kg/ha) and 1-SM (2779 kg/ha) being intermediate. Post-grazing forage biomass was greatest (P = 0.0063) in 3-CM (1982 kg/ha), C (1916 kg/ha), 1-SM (1900 kg/ha), but lower in 3-SM (1592 kg/ha). Prior to grazing, body condition score (BCS) was higher (P = 0.0029) for animals grazing C (5.48), but change in BCS of animals within treatments was not different (P = 0.798). Hair shedding scores (HS) were not different on d-0, with all treatments near 5. However, HS were highest (P < 0.0001) in C (4.75), and lowest in 1-SM (1.75), 3-SM (2), and 3-CM (2) after 56-d. Data suggest animal performance for NE was improved compared to TF during spring grazing in years following renovation. [ABSTRACT FROM AUTHOR]