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Woody encroachment—the spread of woody vegetation in open ecosystems—is a common threat to grasslands worldwide. Reversing encroachment can be exceedingly difficult once shrubs become established, particularly clonal species that resprout following disturbance. Single stressors are unlikely to reverse woody encroachment, but using multiple stressors in tandem could be successful in slowing or reversing encroachment. We explored whether increasing fire frequency in conjunction with multi-year drought could reduce growth and survival of encroaching shrubs in a tallgrass prairie in northeastern Kansas, USA. Passive rainout shelters (~ 50% rainfall reduction) were constructed over mature clonal shrubs (Cornus drummondii) and co-existing C4 grasses in two fire treatments (1-year and 4-year burn frequency). Leaf- and whole-plant level physiological responses to drought and fire frequency were monitored in shrubs and grasses from 2019 to 2022. Shrub biomass and stem density following fire were unaffected by five years of consecutive drought treatment, regardless of fire frequency. The drought treatment had more negative effects on grass leaf water potential and photosynthetic rates compared to shrubs. Shrub photosynthetic rates were remarkably stable across each growing season. Overall, we found that five consecutive years of moderate drought in combination with fire was not sufficient to reduce biomass production or stem density in an encroaching clonal shrub (C. drummondii). These results suggest that moderate but chronic press-drought events do not sufficiently stress encroaching clonal shrubs to negatively impact their resilience following fire events, even when fire frequency is high. [ABSTRACT FROM AUTHOR]

Background. Fire modulates herbivore dynamics in open ecosystems. While extensive work demonstrates the interaction between fire and vertebrate grazers, less research describes how grasshopper herbivory dynamics respond to fire. Aim. We examined how fire increased grass crude protein content and increased the density of and offtake by grasshoppers relative to unburned mixed-grass prairie. Methods. We deployed grasshopper exclusion cages to determine grasshopper offtake of aboveground plant biomass, counted grasshopper abundance throughout the study period, and measured crude protein content of aboveground grass biomass. Key results. Offtake and density were higher in burned versus unburned plots. Burned plot grasshopper density increased over time, with greater rates of increase in recently burned plots, while density remained constant in unburned locations. Conclusions. We present a potential mechanism by which fire interacts with grasshoppers in open ecosystems. It is likely that greater grasshopper offtake and density in recently-burned plots is at least partially attributable to higher crude protein content, as grass in these plots has a much higher proportion of recent growth after fire removed senesced material. Implications. Grasshopper herbivory likely acts as a multiplier of livestock herbivory in burned rangeland. Restoring fire regimes can balance direct negative effects of heating against nutritional benefits. [ABSTRACT FROM AUTHOR]

Silver sagebrush (Artemisia cana) is a low shrub species that is common in northern mixed grass prairies and that provides important wildlife habitat. Silver sagebrush habitat has historically experienced frequent wildfires, but postsettlement fire control efforts have reduced fire frequencies. The effects of fire on silver sagebrush growth and regenera¬tion are not clearly understood; this study examined the effects of fire on silver sagebrush regeneration by evaluating post- fire plant size and distribution data from one season. Sites were located in the northern mixed prairie in Saskatchewan, Canada, and included pastures where the plant community was recovering from both prescribed fires and an intense wildfire. Silver sagebrush responded to fire by producing new shoots via rhizomes, with some plants also regenerating from the crown. No seedlings were observed. Larger plants and dense stands of silver sagebrush appeared to regenerate more successfully than did thin stands. These results demonstrated that silver sagebrush recovery is primarily vegetative, with clone mortality rare. [ABSTRACT FROM AUTHOR]

Fire metrics such as fire front location and rate of spread (ROS) are critical to understanding the behavior of prescribed fires and wildfires. This paper proposes a new method for prescribed grass fire evolution mapping and ROS measurement using multitemporal thermal orthomosaics collected by a small fixed-wing Unmanned Aircraft System (UAS) at low altitudes. The proposed method provides a low-cost, safe, and effective solution for active grass fire monitoring and fire metric measurement in areas that may be challenging for a typical rotor-wing UAS to cover due to endurance and size constraints. The proposed method is demonstrated using a prescribed grass fire data set collected by the KHawk fixed-wing UAS over a 13 ha. Kansas tallgrass prairie field on 8 October 2019. Repeat-pass thermal images collected by the KHawk UAS during about 10 min of the burning were grouped and processed to produce multitemporal orthomosaics with a spatial resolution of about 0 ˜.23 m and a horizontal position error of about 1.5 m. The resulting orthomosaics were further processed for fire front extraction and the measurement of fire front location and ROS. The head fire ROS of this grass burn was observed to be between 0.2 and 0.4 m s − 1 with a mean value of 0.27 m s − 1 . [ABSTRACT FROM AUTHOR]

This article examines the meaning and importance of the dystopian images and symbols used in The Prairie by J.F. Cooper. It also examines the distinctive features of the settings of the novel and its characteristics, as well as the methods and techniques used to depict the prairie as a post-apocalyptic landscape. The author employs these techniques in the use of maritime imagery, as well as gothic and dystopian imagery. The importance of the setting of the novel in explaining the author's attitude toward the causes and beginning of the catastrophe is also discussed in this article. It implies that humanity, rather than divine will, is to blame for the catastrophe, the extremely damaging activities and actions of human being are the leading causes of the world becoming desolate and unpopulated. The bull slaughter and the grasslands firing, are the Cooper's the most powerful and dystopian scenes which are examined in this paper to highlight this point. These scenes appear to highlight Cooper's message about the dangers and hazards of irresponsible ecological devastation. This paper argues that The Prairie is Cooper's the most pessimistic novel that heralds the end of Cooper's ideal fables, based on the repeated use of dystopian terms, symbols, and references. [ABSTRACT FROM AUTHOR]

Tallgrass prairie is a disturbance‐dependent ecosystem that has suffered steep declines in the midwestern United States. The necessity of disturbance, typically fire or grazing, presents challenges to managers who must apply them on increasingly small and fragmented parcels. The goal of this study was to compare effects of management using cattle grazing or fire on vegetation and soil characteristics to aid managers in making decisions regarding the kind of disturbance to apply. We selected 73 sites, of which 27 were managed solely by cattle grazing and 46 solely by fire, for at least 11 yr leading up to the study. We stratified the sites by prairie type (dry, mesic, and wet) and sampled frequency of plant species on randomly placed transects, supplemented with botanist‐directed walks, and collected and composited five soil cores on a randomly selected transect within each prairie type at each site. We calculated rarefied richness and Shannon evenness from the transect data and mean coefficient of conservatism (CofC) from the total list of species. Soil samples were analyzed for texture, bulk density, total N and C, and potential net N nitrification and mineralization. A nonmetric multidimensional scaling analysis of the plant community data revealed differences in species associated with mesic and wet prairies, but no separation by management type. Similarly, none of the vegetation variables we calculated varied by management type, as determined by mixed‐effects models, but soil bulk density was 17.5% higher and total N was 22% higher on grazed sites than burned sites. Sites burned more recently had higher species richness and mean CofC, but fire was not associated with any soil variables. Sites grazed more recently had higher bulk density, total N and C, and faster N cycling rates. Overall, 28% of plant species were found exclusively in one management type or the other, but these species did not vary in mean CofC. We conclude that, at the levels of burning and grazing intensity we studied, both management approaches produce similar C storage and vegetation responses. To maintain maximum diversity across the landscape, however, both approaches are necessary. [ABSTRACT FROM AUTHOR]

The silphium borer moth (Papaipema silphii), a rare endemic insect in midwestern prairies, completes one life cycle per year and has a short dispersal distance. The moth eggs are presumably laid in the duff near host Silphium plants. Silphium species distributions are primarily restricted to fragmented prairie patches, commonly in upland habitats that can burn more intensely than lowland patches. Thus, these moths must cope with existence in a fire-prone environment. Currently, there is controversy regarding how prescribed fire affects the sustainability of prairie invertebrate populations. We counted larval densities of silphium borer moths within thirty-four 0.1-ha plots in three isolated southern Wisconsin prairies with different burn patterns. The median density of larvae was significantly lower in the rotationally burned prairie than in one of the prairies that has been repeatedly burned edge-to-edge. Larval densities did not differ significantly between recently burned and recently unburned plots. These findings suggest that prescribed fires are not endangering the silphium borer moth, regardless of burn method, at least at these three sites. However, more studies at more locations are needed. We still recommend burning only two-thirds of isolated prairies every year. [ABSTRACT FROM AUTHOR]

The microenvironmental effects of spring, summer and autumn burns were investigated for a small area of fescue prairie in Saskatchewan over two growing seasons. Maximum fire temperature in all burns exceeded 300°C at a height of 5-10 cm in the canopy. At a depth of 1 cm in the soil, temperature increased to 40°C during the summer burn, but was unaffected by burns at other seasons. Spring-burned grasses recovered to the same height as the unburned control plot by the end of the first summer. Grass height was similar in all plots by the end of the second growing season, but aboveground biomass in all burned plots was about half that of the control. Graminoid leaf area index at the end of the second growing season ranged from 0.65 in the control plot to 0.27 in the autumn burn. Surface albedos dropped to about 0.03 immediately after burning and took about 3 months to return to the pre-burn values near 0.20. By mid-June of the second year, albedos were similar in all plots. Soil temperatures at 50 cm depth in the burned plots were higher than in the control during the first summer and lower during the winter. The greatest winter snowpack (73 mm water equivalent) accumulated in the control, compared to 48, 35 and 25 mm in the spring, summer and autumn burned plots, respectively. In the first growing season the greatest demand for water occurred in the spring plot followed by the summer, control and autumn plots. In the second season water demand did not differ significantly among plots, reflecting the similarities in plant cover. The microenvironmental effects of a single burning episode in fescue prairie disappear rather quickly, so that there is little long-term impact on the vegetation. [ABSTRACT FROM AUTHOR]

Focuses on the reduction in the amount of tallgrass prairie in North America. Study conducted by the International Biological Program; The three dominant warm-grasses which tallgrass prairie is divided into; Reasons why tallgrass prairie flourished; Effects of prairie fires on nitrogen levels; Efforts to remove detritus.