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Soil microbial communities can play a large role in plant fitness, including plants' response to drought. How microbes mediate drought response may also differ across the plants' life stage, but studies rarely study causal effects of microbes on plant fitness at multiple stages. We conducted a greenhouse experiment on switchgrass (Panicum virgatum L.) to investigate how microbial presence (sterile bulk vs. live bulk soils) and microbial source (communities from bulk vs. rhizosphere soil) affect germination and seedling growth (life-stage) during drought. We also investigated how drought and life-stage alter the assembly of the inoculated communities. Both drought conditions and the absence of microbes reduced germination (49% and 50% fewer seedlings, respectively, p < 0.05), but there were few effects of microbial presence on older seedlings. In addition, microbial source had no effect on the evaluated plant traits, but interestingly, the initially similar bulk and rhizosphere communities became compositionally distinct after 34 days with germinating seeds, but not with seedlings. Therefore, it may be that the plants did respond to microbial source through changes in seed or root exudates, and calls for further study. Finally, while sometimes microbes did benefit plants under drought, we did not find evidence that they are especially beneficial in this condition. We suggest that microbes’ effects differ across plant life stage, and may be both positive and negative. Further research should advance understanding of plant stress tolerance within a framework of plant-microbiome co-development. 

Abstract No-till farming can improve soil health and reduce production costs, yet national adoption remains low, in part because producers face uncertainty about its long-term economic returns. Using more than 30 years of plot-level data from field experiments in Ohio and Michigan, we estimate site-specific effects of no-till on yields and input costs and calculate net profitability using partial budgeting. Results show that no-till consistently reduces operational costs across all sites. In Michigan, no-till also increases yields by 15.6 bu/ac for corn and 5.9 bu/ac for soybean. Estimated net return gains range from approximately $34 to $93 per acre for corn and $30 to $86 per acre for soybean. These results indicate that continuous no-till can generate positive long-run economic returns under the experimental conditions studied, although the magnitude varies across sites and crops. 

The thawing of Arctic permafrost mobilizes previously sequestered carbon, amplifying positive feedback in the global climate system. Thaw patterns are heterogeneous and influenced by factors such as snow insulation and hillslope hydrology, including narrow (<10 m) features like water tracks (WTs) and thermoerosional gullies (TGs). These WT/TG features are distinguished by vegetation, soil moisture, and drainage patterns, yet their snow duration characteristics remain poorly understood. We applied the Blue Snow Threshold (BST) algorithm to high-resolution PlanetScope imagery (3 m) from 2017 to 2023 to quantify snow-on, snow-off, and snow cover duration for 34 field-delineated WTs and TGs on the North Slope of Alaska, USA. BST-derived snow duration metrics were compared to those derived from in situ time-lapse photographs. BST-derived results indicate that snow-on dates are similar between hillslopes and WT/TG features, while snow-off dates are delayed on average by 19 days in WTs and 32 days in TGs. Results from in situ photographs suggest a smaller offset in snow-off dates, 9 days on average, highlighting limitations of the remote sensing data’s temporal resolution. Despite these limitations, these findings suggest that WTs and TGs hold snow longer than the surrounding hillslope, which could facilitate their remote identification and clarify their contributions to permafrost thaw. 

The potential for healthy soils to address goals of productivity and sustainability has motivated a global soil health movement. Though this movement involves many groups, farmers’ perceptions are particularly important because they influence whether and how soil health concepts are practiced on farms. We used surveys of Michigan row crop farmers, followed by cognitive mapping exercises and interviews with a smaller subset of farmers, to describe how farmers understand, manage, and evaluate soil health. We report three key findings. First, we found that Michigan farmers believe in the benefits of soil health, but they are less certain of how to manage soil health on-farm. In particular, farmers found it challenging to evaluate how practices alter soil properties they know are important for soil health, including organic matter, compaction, and soil biology. Second, we found that most Michigan farmers are taking steps to improve the health of soils they farm, which was reflected in their current practices. Use of no-till and cover crops was especially prominent, and decisions to utilize them were motivated by yield benefits and water management. Third, we show that farmers primarily assess soil health with traditional agronomic soil tests and qualitative indicators (e.g., yield, crop coloration, and soil texture), which have strong ties to soil type. Overall, our findings emphasize that while Michigan farmers agree on the key properties and outcomes of healthy soils, they are less certain of how their management translates into improved soil health on-farm. Developing faster-responding, outcome-focused indicators as well as local benchmarks guided by soil type may motivate future adoption and retention of soil health practices.