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Whose everyday? Whose place? This chapter examines the moral assumptions that anchor the different senses of justice concerning Drakes Estero, located in largely rural and agricultural Marin County, California, Point Reyes National Seashore. Vociferous opposition riddled local communities and spread throughout the region over whether a locally popular, family owner–operated oyster company should be allowed to stay once its federal permits for its terrestrial operations expired, and over whether Drakes Estero, legally designated as potential wilderness, should be allowed to become actual wilderness. This chapter investigates the wide array of notions about just and unjust uses of Drakes Estero manifested in the public sphere and the courtrooms, paying particular attention to the moralities that shaped the conflicts over jobs, ways of life, wilderness, environment, and justice. This conflict illuminates the ways in which contentious notions about uses of US public lands are, for all of their differences, premised on a shared perpetuating of the foundational social relations of what Durkheim calls non-integrative social solidarity. Taken in the larger context of contemporary conflicts over US public lands, this particular conflict leads us to query the forms of civics that arise from the social and legal processes of justice already in place.
In recent years, unmanned aerial vehicle (UAV) technology has expanded to include UAV sprayers capable of applying pesticides. Very little research has been conducted to optimize application parameters and measure the potential of off-target movement from UAV-based pesticide applications. Field experiments were conducted in Raleigh, NC during spring 2018 to characterize the effect of different application speeds and nozzle types on target area coverage and uniformity of UAV applications. The highest coverage was achieved with an application speed of 1 m s−1 and ranged from 30% to 60%, whereas applications at 7 m s−1 yielded 13% to 22% coverage. Coverage consistently decreased as application speed increased across all nozzles, with extended-range flat-spray nozzles declining at a faster rate than air-induction nozzles, likely due to higher drift. Experiments measuring the drift potential of UAV-applied pesticides using extended-range flat spray, air-induction flat-spray, turbo air–induction flat-spray, and hollow-cone nozzles under 0, 2, 4, 7, and 9 m s−1 perpendicular wind conditions in the immediate 1.75 m above the target were conducted in the absence of natural wind. Off-target movement was observed under all perpendicular wind conditions with all nozzles tested but was nondetectable beyond 5 m away from the target. Coverage from all nozzles exhibited a concave-shaped curve in response to the increasing perpendicular wind speed due to turbulence. The maximum target coverage in drift studies was observed when the perpendicular wind was 0 and 8.94 m s−1, but higher turbulence at the two highest perpendicular wind speeds (6.71 and 8.94 m s−1) increased coverage variability, whereas the lowest variability was observed at 2.24 m s−1 wind speed. Results suggested that air-induction flat-spray and turbo air–induction flat-spray nozzles and an application speed of 3 m s−1 provided an adequate coverage of target areas while minimizing off-target movement risk.
During the 2015, 2016, and 2017 growing seasons, weed and weed-free mixed tall fescue and legume forage samples were harvested from 29 pastures throughout Missouri for investigation of the nutritive value of 20 common pasture weed species throughout the season. At certain times during the growing season, many broadleaf weed species had greater nutritive values for a given quality parameter as compared with the available weed-free, mixed tall fescue and legume forage harvested from the same location. There were no significant differences in crude protein concentration between the weed-free forage and many weeds throughout the growing season. However, crude protein content of common burdock, common cocklebur, common ragweed, dandelion, horsenettle, and lanceleaf ragweed was greater than that of the corresponding forage sample at multiple collection periods. The digestible neutral detergent fiber (dNDF) content of all broadleaf weeds except lanceleaf ragweed was significantly lower than that of the weed-free forage at all collection periods. Conversely, large crabgrass had significantly greater digestible neutral detergent fiber levels than did the mixed tall fescue forage at all sampling dates. Dandelion and spiny amaranth had greater in vitro true digestibility (IVTD) content than did the forage for the entire growing season. Three perennial weeds—horsenettle, vervains, and late boneset—did not differ in IVTD levels as compared with the mixed tall fescue and legume forage at any collection date. For most summer annual weeds, the trend was toward greater digestibility earlier in the season, with a gradual decline and often lower IVTD by the late summer or early fall. The results of this study will enable producers to make more informed management decisions about the potential benefit or detriment a weed may provide to the overall nutritive value of the pasture system.
Weeds can cause significant yield loss in watermelon production systems. Commercially acceptable weed control is difficult to achieve, even with heavy reliance on herbicides. A study was conducted to evaluate a spring-seeded cereal rye cover crop with different herbicide application timings for weed management between row middles in watermelon production systems. Common lambsquarters and pigweed species (namely, Palmer amaranth and smooth pigweed) densities and biomasses were often lower with cereal rye compared with no cereal rye, regardless of herbicide treatment. The presence of cereal rye did not negatively influence the number of marketable watermelon fruit, but average marketable fruit weight in cereal rye versus no cereal rye treatments varied by location. These results demonstrate that a spring-seeded cereal rye cover crop can help reduce weed density and weed biomass, and potentially enhance overall weed control. Cereal rye alone did not provide full-season weed control, so additional research is needed to determine the best methods to integrate spring cover cropping with other weed management tactics in watermelon for effective, full-season control.
Nutsedge species are problematic in plastic-mulched vegetable production because of the weed’s rapid reproduction and ability to penetrate the mulch. Vegetable growers rely heavily on halosulfuron to manage nutsedge species; however, the herbicide cannot be applied over mulch before vegetable transplanting due to potential crop injury. This can be problematic when multiple crops are produced on a single mulch installation. Field experiments were conducted to determine the response of broccoli, cabbage, squash, and watermelon to halosulfuron applied on top of mulch prior to transplanting. Halosulfuron at 80 g ai ha−1 was applied 21, 14, 7, and 1 d before planting (DBP), and 160 g ai ha−1 was applied 21 DBP. In all experiments, extending the interval between halosulfuron application and planting reduced crop injury. For squash and watermelon, visual injury, plant diameters/vine runner lengths, marketable fruit weights, and postharvest plant biomass resulted in similar values when applying 80 g ha−1 21 DBP and with the nontreated weed-free control. Reducing this interval increased injury for both crops. Visual crop injury and yield reductions up to 40% occurred, with halosulfuron applied 14, 7, or 1 DBP in squash and 1 DBP in watermelon. Broccoli and cabbage showed greater sensitivity, with injury and plant diameter reductions greater than 15%, even with halosulfuron applied at 80 g ha−1 21 DBP. Experimental results confirm that halosulfuron binds to plastic mulch, remains active, and is slowly released from the mulch over a substantial period, during rainfall or overhead irrigation events. Extending the plant-back interval to at least 21 d before transplanting did overcome squash and watermelon injury concerns with halosulfuron at 80 g ha−1, but not broccoli and cabbage. Applying halosulfuron over mulch to control emerged nutsedge before planting squash and watermelon would be beneficial if adequate rainfall or irrigation and appropriate intervals between application and planting are implemented.
To understand the implications of archaeological site recording practices and associated inventories for studying Indigenous persistence after the arrival of Europeans, we examined the documentary record associated with nearly 900 archaeological sites in Marin County, California. Beginning with the first regional surveys conducted during the early 1900s and continuing into the present, the paper trail created by archaeologists reveals an enduring emphasis on precontact materials to the exclusion of more recent patterns of Indigenous occupation and land use. In assessing sites occupied by Indigenous people from the late sixteenth through the mid-twentieth centuries, we discuss how the use of multiple lines of evidence—including temporally diagnostic artifacts, chronometric dating techniques, and historical documentation—may help illuminate subtle but widespread patterns of Native presence that have been obscured by essentialist assumptions about Indigenous culture change. Our findings further reveal the shortcomings of traditional site recording systems, in which archaeologists typically categorize sites within the prehistoric-protohistoric-historic triad on the basis of commonsense decisions that conflate chronology with identity. Instead, we argue for recording practices that focus specifically on the calendric ages of occupation for any given site.
Goosegrass is considered one of the worst agricultural weeds worldwide. Understanding its life cycle will provide useful management information. Field experiments with six emergence times (April, May, June, July, August, and September) were conducted at Anyang, China in 2015 and 2017 to clarify the growth and reproduction of goosegrass emerging at different times within a season. The result showed that plant height, dry weight, average weight per inflorescence, total inflorescence weight, average seed number per inflorescence, and total number of seeds per plant were relatively low in the April cohort, peaked with the May or June emergence cohort, and decreased thereafter. However, the earliest emergence of goosegrass in April had the highest total number of inflorescences. The plants of the May cohort produced the greatest number of seeds: 225,954 and 322,501 seeds per plant in 2015 and 2017, respectively. Delayed emergence resulted in less seed production; most plants that emerged in September did not flower or set seed. The 1,000-seed weight did not vary among the emergence cohorts. The reproductive investment was lowest for plants of the May cohort and then increased as emergence time was delayed to June, July, and August. Fresh mature seed of all emergence cohorts was extremely dormant and had low germination only up to 6% from August to November, and high germination (44% to 93%) in December. The information gained from this study indicates that weed management strategies should focus on the early-emerged seedlings such as the April and May cohorts, so as to effectively prevent goosegrass seed production, minimize the weed seed replenishment into the soil seed bank, and reduce the infestation in subsequent seasons.
AMS radiocarbon dating of two modified pearls from the Covacha Babisuri site, Espíritu Santo Island, Baja California Sur, México, corroborates associated midden dates suggesting that traditional indigenous use and modification of pearls as items of adornment began at least 8,500 years ago. To our knowledge, these are the oldest modified pearls found in dated archaeological contexts anywhere in the world. The presence of similarly modified pearls in later components at Covacha Babisuri suggests that this custom continued throughout the Middle Holocene, and ethnohistoric accounts indicate that similar modifications of pearls continued up until the Historic Era. These data show a long history of cultural continuity in the region in pearl harvesting, modification, and use as adornment.
Hospital evacuations of patients with special needs are extremely challenging, and it is difficult to train hospital workers for this rare event.
Researchers developed an in-situ simulation study investigating the effect of standardized checklists on the evacuation of a patient under general anesthesia from the operating room (OR) and hypothesized that checklists would improve the completion rate of critical actions and decrease evacuation time.
A vertical evacuation of the high-fidelity manikin (SimMan3G; Laerdal Inc.; Norway) was performed and participants were asked to lead the team and evacuate the manikin to the ground floor after a mock fire alarm. Participants were randomized to two groups: one was given an evacuation checklist (checklist group [CG]) and the other was not (non-checklist group [NCG]). A total of 19 scenarios were run with 28 participants.
Mean scenario time, preparation phase of evacuation, and time to transport the manikin down the stairs did not differ significantly between groups (P = .369, .462, and .935, respectively). The CG group showed significantly better performance of critical actions, including securing the airway, taking additional drug supplies, and taking additional equipment supplies (P = .047, .001, and .001, respectively). In the post-evacuation surveys, 27 out of 28 participants agreed that checklists would improve the evacuation process in a real event.
Standardized checklists increase the completion rate of pre-defined critical actions in evacuations out of the OR, which likely improves patient safety. Checklist use did not have a significant effect on total evacuation time.
Goldenrods are common perennial weeds in lowbush blueberry fields in Nova Scotia. Management options are limited to mowing and suppression with POST mesotrione applications. The objectives of this research were to (1) compare efficacy of single versus sequential nonbearing-year POST mesotrione applications on goldenrod (2) identify the optimal interval between sequential POST mesotrione applications (3) evaluate nonbearing-year POST bicyclopyrone applications on goldenrod, and (4) evaluate nonbearing-year summer and fall herbicide spot treatments on goldenrod. POST mesotrione applications at 144 g ai ha−1 caused 39% to 77% injury but did not reduce goldenrod shoot density. In contrast, mesotrione applications at 144 g ai ha−1 followed by sequential mesotrione application at 14, 21, or 28 days after initial treatment caused greater than 90% injury to goldenrod and reduced both nonbearing- and bearing-year shoot density. POST bicyclopyrone applications at 50 g ai ha−1 caused 69% to 80% injury to goldenrod but did not reduce shoot density. A bicyclopyrone plus mesotrione tank mixture did not improve goldenrod control relative to mesotrione or bicyclopyrone alone. Summer spot applications of glyphosate (7.24 g ae L water−1), glufosinate (0.75 g ai L water−1), and mesotrione (0.72 g ai L water−1) consistently injured goldenrod and reduced both nonbearing- and bearing-year shoot density. Summer spot applications of bicyclopyrone (0.25 g ai L water−1), flazasulfuron (0.31 g ai L water−1), dicamba (1 g ae L water−1), dicamba plus diflufenzopyr (0.7 g ae L water−1 plus 0.3 g ai L water−1), triclopyr (1.68 g ai L water−1), clopyralid (0.08 g ai L water−1), tribenuron methyl (0.2 g ai L water−1), and foramsulfuron (0.2 g ai L water−1) injured goldenrod but did not consistently reduce shoot density. When these herbicides were evaluated as fall spot applications, only glyphosate reduced goldenrod shoot density in the year after application.
Research was conducted from 2013 to 2015 across three sites in Mississippi to evaluate corn response to sublethal paraquat or fomesafen (105 and 35 g ai ha−1, respectively) applied PRE, or to corn at the V1, V3, V5, V7, or V9 growth stages. Fomesafen injury to corn at three d after treatment (DAT) ranged from 0% to 38%, and declined over time. Compared with the nontreated control (NTC), corn height 14 DAT was reduced approximately 15% due to fomesafen exposure at V5 or V7. Exposure at V1 or V7 resulted in 1,220 and 1,110 kg ha−1 yield losses, respectively, compared with the NTC, but yield losses were not observed at any other growth stage. Fomesafen exposure at any growth stage did not affect corn ear length or number of kernel rows relative to the NTC. Paraquat injury to corn ranged from 26% to 65%, depending on growth stage and evaluation interval. Corn exposure to paraquat at V3 or V5 consistently caused greater injury across evaluation intervals, compared with other growth stages. POST timings of paraquat exposure resulted in corn height reductions of 13% to 50%, except at V7, which was most likely due to rapid internode elongation at that stage. Likewise, yield loss occurred after all exposure times of paraquat except PRE, compared with the NTC. Corn yield was reduced 1,740 to 5,120 kg ha−1 compared with the NTC, generally worsening as exposure time was delayed. Paraquat exposure did not reduce corn ear length, compared with the NTC, at any growth stage. However, paraquat exposure at V3 or V5 was associated with reduction of kernel rows by 1.1 and 1.7, respectively, relative to the NTC. Paraquat and fomesafen applications near corn should be avoided if conditions are conducive for off-target movement, because significant injury and yield loss can result.
In a predictable natural selection process, herbicides select for adaptive alleles that allow weed populations to survive. These resistance alleles may be available immediately from the standing genetic variation within the population or may arise from immigration via pollen or seeds from other populations. Moreover, because all populations are constantly generating new mutant genotypes by de novo mutations, resistant mutants may arise spontaneously in any herbicide-sensitive weed population. Recognizing that the relative contribution of each of these three sources of resistance alleles influences what strategies should be applied to counteract herbicide-resistance evolution, we aimed to add experimental information to the resistance evolutionary framework. Specifically, the objectives of this experiment were to determine the de novo mutation rate conferring herbicide resistance in a natural plant population and to test the hypothesis that the mutation rate increases when plants are stressed by sublethal herbicide exposure. We used grain amaranth (Amaranthus hypochondriacus L.) and resistance to acetolactate synthase (ALS)-inhibiting herbicides as a model system to discover spontaneous herbicide-resistant mutants. After screening 70.8 million plants, however, we detected no spontaneous resistant genotypes, indicating the probability of finding a spontaneous ALS-resistant mutant in a given sensitive population is lower than 1.4 × 10−8. This empirically determined upper limit is lower than expected from theoretical calculations based on previous studies. We found no evidence that herbicide stress increased the mutation rate, but were not able to robustly test this hypothesis. The results found in this study indicate that de novo mutations conferring herbicide resistance might occur at lower frequencies than previously expected.
Weedy rice (Oryza spp.) is considered one of the main weeds in cultivated rice (Oryza sativa L.) around the world, having a great impact on both yield and quality of crop rice. Recent studies have characterized the range of morphological and genetic diversity in weedy rice from different locations and have revealed that there is often great morphological diversity within growing regions. No systematic attempt to characterize phenotypic diversity of weedy rice in Colombia, where this group of weeds greatly affects rice production, has yet been carried out. This study seeks (1) to establish the range of variation in various morphological characters for weedy rice collected in the five production zones of Colombia and to compare these with commercial varieties and landraces sown in the country, (2) to determine the association between weedy rice morphotypes and rice production areas in the country, and (3) to assess whether any association exists between morphology and recently discovered genetic groupings for weedy rice in Colombia. Based on a sampling of rice production areas in Colombia and evaluation of 27 phenotypic traits, a two-step cluster analysis identified four morphological groups for weedy rice in Colombia. These groupings had some limited association with geography and the genetic ancestries of weedy rice. Clustering showed that awn and apiculus color and awn length and presence are the most important predictors in defining morphological groupings. Understanding and classifying the morphological diversity may be helpful in understanding weedy rice origins, evolution, and potential management practices.
Broadleaf infestations interfere with Florida strawberry production. Broadleaf POST herbicide options applied atop the crop are limited to synthetic auxins and not suitable for conventional multi-cropping and organic systems. Reducing light access and interception during weed emergence may reduce interference. Light-limited growth of two problematic broadleaves, black medic and Carolina geranium, and the most commonly grown strawberry cultivar (‘Florida Radiance’), were examined in the greenhouse. The experimental design was completely randomized, and the trial was repeated. Black medic was susceptible to reductions in incoming solar radiation, wherein reducing the daily maximum available light from 331 to 94 µmol m−2 s−1 reduced leaf number and area by 93% and 89%, respectively. Carolina geranium growth was less susceptible to reduced-light treatments, with leaf area and number each reduced by 66% when light was reduced from 331 to 94 µmol m−2 s−1. Belowground, Carolina geranium biomass was similarly reduced between the 331 and 94 µmol m−2 s−1 treatments. Strawberry was relatively tolerant to shading at 155 µmol m−2 s−1, but further reductions did increase mortality. Shade-induced weed suppression is a promising alternative strategy for conventional and organic Florida strawberry production. Targeted application during periods of weed emergence may play a role within integrated pest management strategies. This approach is most feasible for black medic management but may be useful for Carolina geranium in concert with other strategies.
Greenhouse and field studies were conducted to determine tolerance of blueberry to saflufenacil. Greenhouse studies included five saflufenacil rates (0, 50, 100, 200, and 400 g ai ha−1) and three southern highbush blueberry cultivars (‘Legacy’, ‘New Hanover’, and ‘O’Neal’) and one rabbiteye blueberry cultivar (‘Columbus’). Saflufenacil treatments were soil applied into each pot when blueberry plants were approximately 30-cm tall. Visible injury (purpling/reddening of foliage and leaf abscission) ranged from 3% to 12%, 3% to 42%, 0% to 43%, and 0% to 29% with saflufenacil from 50 to 400 g ha−1 in Columbus, Legacy, New Hanover, and O’Neal, respectively, at 28 d after treatment. Regardless of injury, plant growth (change in height), soil plant analysis development, and whole-plant dry biomass of all cultivars did not differ among saflufenacil rates. Field studies were conducted in Burgaw, NC, to determine the tolerance of nonbearing (<3-yr-old and not mature enough to produce fruit) and bearing (>3-yr-old and mature enough to produce fruit) southern highbush blueberry (‘Duke’) to saflufenacil application at pre-budbreak or during the vegetative growth stage. Treatments included three rates of saflufenacil (50, 100, and 200 g ha−1), glyphosate (870 g ae ha−1), glufosinate (1096 g ai ha−1), glyphosate (870 g ha−1) + saflufenacil (50 g ha−1), glufosinate (1096 g ha−1) + saflufenacil (50 g ha−1), and hexazinone (1,120 g ai ha−1), applied POST-directed to the soil surface beneath blueberry plants in a 76-cm band on both sides of the blueberry planting row. The maximum injury from treatments containing saflufenacil was ≤11% in both nonbearing and bearing blueberry. No negative effects on plant growth or fruit yield were observed from any treatments. Results from both greenhouse and field studies suggest that saflufenacil applied at 50 (1X commercial use rate) and 100 g ha−1 is safe to use in blueberry.
Linuron herbicide has been a mainstay of carrot weed management for years, but uncertainty around regulatory registration review and an increased prevalence of herbicide-resistant weeds have spurred interest in identifying alternatives that can be readily adopted in production. With this context in mind, herbicide programs were evaluated on a coarse-textured, low organic matter soil in 2015 and 2016. Season-long weed control without compromising yield was possible with weed management programs that included prometryn POST instead of linuron. With that said, a PRE herbicide such as pendimethalin was critical to establish an early-season competitive advantage for carrot plants over weeds, and careful attention should be paid to the prometryn rate, as selectivity is marginal. Carrot is often interseeded with a grain nurse crop to mitigate risk of wind erosion. Nurse crop injury was minimal where S-metolachlor, pendimethalin, or prometryn was applied at rates labeled for PRE use in carrot, with the exception of where prometryn was applied at rates above 1.1 kg ai ha−1.
Studies were conducted at six locations across North Carolina to determine tolerance of ‘Sunbelt’ grape (bunch grape) and muscadine grape (‘Carlos’, ‘Triumph’, ‘Summit’) to indaziflam herbicide. Treatments included indaziflam (0, 50, 73 g ai ha–1) or flumioxazin (213 g ai ha–1) applied alone in April, and sequential applications of indaziflam (36, 50, 73 g ai ha–1) or flumioxazin (213 g ai ha–1) applied in April followed by the same rate applied in June. No crop injury was observed across locations. Muscadine yield was not affected by herbicide treatments. Yield of ‘Sunbelt’ grape increased with sequential applications of indaziflam at 73 g ha–1 when compared to a single application of indaziflam at 50 g ha–1 or flumioxazin at 213 g ha–1 in 2015. Sequential applications of flumioxazin at 213 g ha–1 reduced ‘Sunbelt’ yield compared to a single application of indaziflam at 73 g ha–1 in 2016. Trunk cross-sectional area was unaffected by herbicide treatments. Fruit quality (soluble solids concentration, titratable acidity, and pH) for muscadine and bunch grape was not affected by herbicide treatments. Indaziflam was safe to use at registered rates and could be integrated into weed management programs for southern US vineyards.
Radnor Lake State Natural Area in Nashville, TN, has cedar glades that contain the endangered perennial herb wild dill [Perideridia americana (Nutt. ex DC.) Rchb.] and the invasive shrub Amur honeysuckle [Lonicera maackii (Rupr.) Herder]. This research examined whether L. maackii treatment in the Radnor Lake State Natural Area cedar glades is followed by an increase in P. americana plants. A grid of 60 adjacent 2 m by 4 m plots was placed in five cedar glades to encompass the P. americana population. With great care to protect P. americana, the annual treatment for L. maackii was to pull plants ≤1-m tall from the ground; and to cut stems >1-m tall and then treat the stumps with glyphosate. The t-tests of means for the log natural of the number of plants in the 60 plots (significance level of P-value = 0.05) were used to compare pretreatment L. maackii and P. americana counts with posttreatment counts in 2018 and P. americana counts at leaf out and flowering in 2018. The L. maackii population was significantly smaller (P-value < 0.001) in 2018 than pretreatment at all five sites. When pretreatment in 2014 and 2015 was compared with posttreatment in 2018 for the P. americana populations, the increases were significant at the Cheek, Harris 2, Hideaway, and Norfleet sites, but the increase at East Hall Farm was not significant. White-tailed deer (Odocoileus virginianus Zimmermann) trampling was the explanation given for the decreases in P. americana from leaf out to flowering at all five sites in 2018. Browsing was evident only at Hideaway, which had a greater loss for P. americana from leaf out to flowering in 2018 than the combined losses for the Cheek, East Hall Farm, Harris 2, and Norfleet sites. The research informed the creation of adaptive management decisions regarding monitoring and treatment of the invasive species L. maackii for an endangered species.
In California, invasive grasses have displaced native plants, transforming much of the endemic coastal sage scrub (CSS) to nonnative grasslands. This has occurred for several reasons, including increased competitive ability of invasive grasses and long-term alterations to the soil environment, called legacy effects. Despite the magnitude of this problem, however, it is not well understood how these legacy effects have altered the soil microbial community and, indirectly, native plant restoration. We assessed the microbial composition of soils collected from an uninvaded CSS community (uninvaded soil) and a nearby 10-ha site from which the invasive grass Harding grass (Phalaris aquatica L.) was removed after 11 yr of growth (postinvasive soil). We also measured the survival rate, biomass, and length of three CSS species and P. aquatica grown in both soil types (uninvaded and postinvasive). Our findings indicate that P. aquatica may create microbial legacy effects in the soil that likely cause soil conditions inhibitory to the survival rate, biomass, and length of coastal sagebrush, but not the other two native plant species. Specifically, coastal sagebrush growth was lower in the postinvasive soil, which had more Bacteroidetes, Proteobacteria, Agrobacterium, Bradyrhizobium, Rhizobium (R. leguminosarum), Candidatus koribacter, Candidatus solibacter, and rhizophilic arbuscular mycorrhizal fungi, and fewer Planctomycetes, Acidobacteria, Nitrospira, and Rubrobacter compared with the uninvaded soil. Shifts in soil microbial community composition such as these can have important implications for restoration strategies in postinvasive sites.
Biological invasions are one of the grand challenges facing society, as exotic species introductions continue to rise and can result in dramatic changes to native ecosystems and economies. The scale of the “biological invasions crisis” spans from hyperlocal to international, involving a myriad of actors focused on mitigating and preventing biological invasions. However, the level of engagement among stakeholders and opportunities to collaboratively solve invasives issues in transdisciplinary ways is poorly understood. The Biological Invasions: Confronting a Crisis workshop engaged a broad group of actors working on various aspects of biological invasions in Virginia, USA—researchers, Extension personnel, educators, local, state, and federal agencies, nongovernmental organizations, and land managers—to discuss their respective roles and how they interact with other groups. Through a series of activities, it became clear that despite shared goals, most groups are not engaging with one another, and that enhanced communication and collaboration among groups is key to designing effective solutions. There is strong support for a multistakeholder coalition to affect change in policy, public education/engagement, and solution design. Confronting the biological invasions crisis will increasingly require engagement among stakeholders.