Hairy vetch decomposed faster than cereal rye. Hairy vetch released N within two weeks of termination. Biomass belowground decomposed more quickly than aboveground. Cover crop N release occurred earlier than maximum crop uptake due to late planting. Synchronizing cover crop decomposition and nutrient release with cash crop uptake can provide benefits to agroecosystems but can be difficult to implement. The objectives of this study were to quantify the aboveground and belowground decomposition and nutrient release of two cover crops, hairy vetch (Vicia villosa Roth) and cereal rye (Secale cereale L.), after termination with herbicides through a 16‐wk period during the cash crop growing season using litterbags and intact root cores. Plant Root Simulator probes monitored mineral N in the soil. Hairy vetch aboveground (k = 0.4505) and root (k = 0.6821) biomass decomposed at a faster rate than aboveground (k = 0.1368) and root (k = 0.1866) biomass of cereal rye. Hairy vetch had higher initial N content in aboveground (41.9 g kg–1) and root (16.5 g kg–1) biomass than cereal rye (11.5 and 8.3 g kg–1, respectively). Hairy vetch had a lower C to N ratio than cereal rye in both aboveground (9.52 vs. 34.72) and root biomass (17.31 vs. 40.31) contributing to decomposition differences. Hairy vetch rapidly decomposed after cover crop termination in the spring, therefore growers should consider delaying termination of this cover crop until close to cash crop planting to decrease the risk of N loss. Cereal rye residues decompose much slower and may also immobilize N because of its high C to N ratio. A better understanding of how aboveground and belowground cover crop characteristics influence decomposition will help to optimize cover crop nutrient release with cash crop uptake.

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Tillage and fertilization are common practices used to enhance soil fertility and increase yield. Changes in soil edaphic properties associated with different tillage and fertility regimes have been widely examined, yet, the microbially mediated pathways and ecological niches involved in enhancing soil fertility are poorly understood. The effects of long-term conventional tillage and no-till in parallel with three fertility treatments (No fertilization, N-only, and NPK) on soil microbial communities were investigated in a long-term field study that was established in the 1970's. Here, we used highthroughput sequencing of bacterial, fungal and oomycetes markers, followed by community-level functional and ecological assembly to discern principles governing tillage and fertility practices' influence on associated soil microbiomes. Both tillage and fertilizer significantly altered microbial community structure, but the tillage effect was more prominent than the fertilizer effect. Tillage significantly affected bacteria, fungi, fusaria, and oomycete beta-diversity, whereas fertilizer only affected bacteria and fungi beta-diversity. In our study different tillage and fertilizer regimes favored specific networks of metabolic pathways and distinct ecological guilds. No-till selected for beneficial microbes that translocate nutrients and resources and protect the host against pathogens. Notably, ecological guilds featuring arbuscular mycorrhizae, mycoparasites, and nematophagous fungi were favored in no-till soils, while fungal saprotrophs and plant pathogens dominated in tilled soils. Conventional till and fertilizer management shifted the communities toward fast growing competitors. Copiotrophic bacteria and fusarium species were favored under conventional tillage and in the presence of fertilizers. The analysis of the metagenomes revealed a higher abundance of predicted pathways associated with energy metabolism, translation, metabolism of cofactors and vitamins, glycan biosynthesis and nucleotide metabolism in no-till. Furthermore, no specific pathways were found to be enriched under the investigated fertilization

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Reducing soil disturbance may limit erosion, but many still consider tillage essential for seedbed preparation, particularly on poorly drained soils. ) and fi ve fertilizer (no fertilization, N-only, N+NPK starter, NPK+NPK starter, and NPK broadcast) treatments were evaluated. With N, P, and K fertilizer, yields were similar for tilled and NT treatments, averaging 8.73 Mg ha -1 for CC and 11.93 Mg ha -1 and 3.70 Mg ha -1 for rotated corn and soybean. Below recommended soil-test values resulted in NT yielding less than tilled treatments even though soil test P, K, and pH were similar. No-till with N, P, and K increased soil organic matter (OM) to 27.6 g kg -1 (20.5 g kg -1 in all other treatments), with the greatest increase from 0-to 5-cm. No-till treatments showed stratifi cation of P and K, but it had no eff ect on yield. No excessive pH stratifi cation was observed. Overall, fertilizer management predominantly infl uenced crop yield and with complete NPK management non-tilled yields were similar to tilled, even on fl at, somewhat-poorly drained soils. No-till with NPK management therefore may allow farmers to maintain high yields while reducing soil and nutrient losses. R.L. Cook,