The limestone bluffs of the central Mississippi River Valley represent a significant portion of the remaining intermingled xeric hill prairie-savanna-woodland systems of the Midwest where different cover types may co-occur at very fine scales. Efforts to restore these landscapes would benefit from a data-driven tool to delineate existing vegetation cover characteristics and reconcile these with desired management outcomes on a spatially explicit basis. This study employed hierarchical cluster analysis and nonmetric multidimensional scaling in combination with indicator species analysis and dendrochronological methods to examine the structure, composition, and temporal community patterns of the forest–prairie gradient in the Mississippi River Bluffs of Jersey County, Illinois. Four distinct community types were identified on the gradient: (1) a woodland community dominated by Juniperus virginiana, Carya glabra, Quercus stellata, and Lonicera maackii; (2) open oak woodland with high exposed soil and overstory of Acer saccharum, Q. velutina, and Q. muehlenbergii; (3) a hill prairie community with grass coverage as the sole indicator; and (4) a transitioning community with 14 significant indicators and a trajectory advancing toward mesophytic forest composition. These data, within context with stem age, historical documents, and drought data, reveal the role of historical disturbances in temporal patterns of forest–prairie dynamics and provide a resolution in greater detail than previous studies of forest and nonnative invasive shrub encroachment. Pairing management activities to stand conditions, as informed by understanding drivers of ecosystem change, provides continuity with historical disturbance regimes and an objective basis for restoration activities and targets.

Invasive plant species can have significant, adverse effects on forest ecosystems. By outcompeting native species for resources, invasive species suppress the richness and diversity of many forest communities. This study focuses on the associations of Amur honeysuckle (Lonicera maackii Rupr.) with spring flora in Raven Run Nature Sanctuary in Lexington, Kentucky, where abundant L. maackii threatens native biodiversity. Plots were surveyed for percent herbaceous groundcover and abundance of flowering spring flora at three levels of L. maackii density (high, low, and no L. maackii). Results indicate that L. maackii abundance is associated with lower species richness, abundance, and early-season diversity of flowering native spring flora. Importantly, this study extends the existing robust literature evaluating the widespread effects of L. maackii to the Kentucky River Palisades, a sensitive and botanically important corridor in central Kentucky.

The pine rocklands of southern Florida are an imperiled habitat as the higher, drier areas of land have been steadily developed over the last century. Little of the original extent of this unique ecosystem remains today, with much of it in remnant fragments affected by surrounding development. With this study, we sought to investigate temporal changes in diversity of pine rockland Fabaceae induced by anthropogenic factors. We provide a status update for Fabaceae taxa, a diverse and important group of plants in pine rocklands. Herbarium collections (1339 records) spanning 175 y (from 1830 to 2015) were used to analyze the species frequency and richness of plants collected. The results indicated temporal fluctuations in collection diversity with frequency of native species highest prior to the year 1920, and nonnative legume richness increasing with the decades. The accompanying species list resulting from the inventory included 119 Fabaceae species, in 52 genera, with an additional 18 species not previously listed for pine rocklands. Many other studies have documented the change in pine rockland cover and its extreme extent of habitat loss and fragmentation as the result of human development and population growth. The results of this study document the indirect effects of human habitation on remnant natural areas, as evidenced by collections from Miami-Dade County, with exotic invasives increasingly represented over time. The results also document the historical distributions of collections of Fabaceae species, helpful to conservation and restoration efforts in the globally imperiled pine rocklands of southern Florida.

We examined a study plot sampled in the Conecuh National Forest of southern Alabama in 1999 and again in 2016 after stand thinning and persistent prescribed fire were used to improve habitat quality. These management activities were designed, in part, to enhance habitat quality for the gopher tortoise (Gopherus polyphemus), a species considered for protection under the Endangered Species Act because of range-wide population declines. Comparisons of vegetation structure were made at burrows that were active in 1999 and remained active in 2016, and at burrows that were active in 1999 but were classified as abandoned in 2016. Burrows that remained active across this span of time were distinctive in retaining a greater reduction of canopy cover and lacking hardwoods while having a high percentage of longleaf pine in neighboring canopy trees. Active burrows that were abandoned in 2016 were distinctive in possessing hardwoods among neighboring canopy trees, lacking pine seedlings in the midstory, and having increased frequency of legumes and decreased bare ground in the understory. All burrows experienced a decrease in canopy cover and an increase in distance to, and dbh of, neighboring canopy trees; all burrows also had a decrease in litter and non-legume forbs as well as an increase in shrub stems in the understory and midstory. These results indicate that management activities were successful in opening canopy cover but were largely unsuccessful at reducing shrub stems and increasing understory grasses and forbs. Nevertheless, burrows of gopher tortoises increased in abundance during this time period. The size distribution of these burrows changed from a unimodal distribution dominated by adults to a bimodal distribution indicative of increased juvenile recruitment. Thus, the gopher tortoise population increased in association with vegetation changes that suggest tortoises are more sensitive to shading caused by canopy closure than they are to available forage.

We conducted literature searches of records from Illinois, Indiana, Iowa, Minnesota, Missouri, North Dakota, Ohio, and Wisconsin to create a source bibliography of wildland fire descriptions occurring between 1673 and 1905. A total of 795 landscape fire records were identified within or near the eastern tallgrass prairie–forest transition region, including 32 attributed to Native Americans, 194 to Europeans from spontaneous records in the nineteenth century, and 569 to Europeans from a systematic dataset collected during the late nineteenth and early twentieth centuries in Minnesota. From these historical accounts, we find overwhelming evidence that a two- to three-week period during October and November, known then as “Indian summer,” was the primary wildland fire season. Our records indicate that Native Americans used fire primarily for hunting, whereas Euro-American fires were set to reduce fire hazards near their habitations, to eliminate crop residues, and to facilitate plowing, or they were escapes due to mere carelessness. Only five lightning-caused fires were identified. Individual fires frequently burned thousands of hectares, creating dense smoke, damaging trees, personal property, and occasionally burning inhabitants fatally. South and southwest were the most frequent wind directions during wildfires. Drought years, including 1796, 1819, 1856, and 1871, were characterized by extensive fires, which ultimately resulted in legislation to protect property owners and public welfare. Fire events for the study period are certainly underestimated by this dataset because only large, spectacular, threatening fires were recorded, especially during European settlement. In addition, our estimate of Native American fire frequency and prevalence is less than their historical/expected frequency, due to their widespread population collapse and changed hunting methods following contact and dispossession by Europeans.

Smooth brome (Bromus inermis Leyss.) has been planted widely for use as a forage grass and erosion control. Its competitive nature and rapid growth have allowed smooth brome to become an invasive species throughout the Northern Great Plains. Prescribed burning is commonly employed to control smooth brome in the region's remaining native grasslands. Burning at the initiation of elongation, when smooth brome populations are most vulnerable, destroys the carbohydrate reserves that allow the plants to recover. Identifying the five-leaf stage in phenological development has been recommended to signal the start of elongation in order to time prescribed burning to be most detrimental to smooth brome. Unfortunately, in a recent field survey of 27 sites in the Northern Great Plains, less than 1% of smooth brome tillers were observed to achieve the five-leaf stage prior to elongation, calling the tying of prescribed burning to identification of the five-leaf developmental stage into question. Accumulated growing degree days (AGDD) provides a more reliable indicator of smooth brome's vulnerability to control efforts through prescribed burning than reliance on the observance of the five-leaf stage. This study was designed to monitor phenological development of smooth brome in a controlled greenhouse environment to determine whether the correlation between AGDD and phenological development was exhibited in greenhouse populations across a gradient of nitrogen conditions encountered throughout the Northern Great Plains. It was determined that, while nitrogen treatment did affect the biomass and number of tillers produced, it did not affect the phenological progression of development. The greenhouse population reached 50% elongation at an average of 2287 AGDD.

Invasive species are a major threat to natural ecosystems. To combat the destructive potential of arriving invasive species, many natural resource managers have adopted an “early detection and rapid response” (EDRR) strategy. A key component of EDRR is a “watch list” of invasive species that have yet to be detected in a managed area and are prioritized for surveillance, reporting, and other responses. However, managed areas with limited resources may not have the capacity to develop useful watch lists. To address this need, we developed an automated process to use data from iNaturalist, a popular citizen science platform, and a United States national list of nonnative plant species to compile a provisional watch list of the 100 most frequently reported nonnative species within a 160 km buffer around a managed area. We demonstrated the application of the process using 36 US National Park Service units with relatively small operating budgets. Using Fort Vancouver National Historic Site, Washington, as an example, we show how provisional watch lists can be refined by removing species that are unlikely to occur in the unit due to the absence of suitable habitat and prioritizing species from the state priority invasive plant list. The automated process has the advantage of being easily repeatable at regular intervals to alert managers of newly arrived species. Managers can readily modify this method for use anywhere if they have access to observation data from a citizen science platform and a list of nonnative species in the area of interest.

Approximately 2600 km of bison and elk trails have been mapped in West Virginia using historical records, including county histories and travelers' accounts with published dates between 1876 and 1977. Most points of interest associated with these trails document European bison or elk hunting events. We explore some potential uses of the digital trails data and discuss the limitations of the data and need for further refinements. This map of major bison trails (available for download at https://doi.org/10.2737/RDS-2021-0055) is an important resource for telling a more complete story of the history of forests and woodlands of West Virginia.