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Questions:Restoration of grassy biomes is currently of large importance, and controlling invasive grasses is often key to restoring these ecosystems in the tropics and subtropics. We combined different ecological restoration techniques to evaluate potential to control the invasive grass Urochloa decumbens and restore plant species composition. Specific questions were: (a) are herbicide application and topsoil removal efficient to control U. decumbens cover and allow native species establishment; and (b) are hay transfer and sowing native grass species efficient to reintroduce native species and increase their cover? Location: Campos grasslands, southern Brazil. Methods: We combined the follow restoration techniques: (a) herbicide application or topsoil removal to control the invasive species, and (b) hay transfer or sowing of native grasses to reintroduce native species. We assessed and compared native plant species richness, vegetation cover, native species cover, U. decumbens cover and other exotic species cover in 2016 and 2017.Results: Herbicide application reduced invasive species cover more than topsoil removal, even though both were effective. The decrease of U. decumbens cover led to an increase in native species cover and native species richness. Hay transfer and sowing native grasses did not produce satisfactory results for native species reintroduction. Native species richness and U. decumbens cover increased from 2016 to 2017. Conclusion:Herbicide application was a better option to control U. decumbens and to allow recovery of native species. However, use of herbicides in restoration is controversial, and more detailed studies on impacts are necessary. Environmental filters appear to be a major cause for failure of hay transfer and seeding species. Recovery of the native plant community is a great challenge in invaded subtropical grasslands, and additional management actions and time are necessary to increase the establishment of native species.

Abstract. The New York Botanical Garden occupies 100 hectares (250 acres) in the north central portion of Bronx County, New York. The property is a public garden with the majority of the grounds under cultivation. The Thain Family Forest, margins of the Bronx River, rock outcrops and areas of undeveloped landscape are important refugia for spontaneous plants, both native and non-native. We compiled data from historic lists of spontaneously occurring species, conducted original field work and searched the William and Lynda Steere Herbarium to determine the historic and extant spontaneous vascular plant flora of the Garden from 1899 to 2015. This is the first published inventory of the wild flora since 1899. The historic and extant flora comprises 695 species and infraspecies in 363 genera and 121 families. The extant flora comprises 429 species and infraspecies in 263 genera and 108 families. A total of 264 (62%) of the extant species and infraspecies are native and 165 (38%) are not native. All species are vouchered by herbarium specimens collected between 1881 and 2015. All herbarium vouchers are databased, imaged and available online. Forty-six species and infraspecies are new Bronx County records. Among the rare extant species and infraspecies on the New York State Department of Environmental Conservation Active Inventory List are three critically imperiled (S1) and two imperiled (S2) taxa, and Carex aggregata that was thought to be historical (SH, no existing sites known) in New York State, but was found in 2009 on the grounds. The number of extant rare species and infraspecies, the total number of extant taxa and the percentage of native verus non-native species strongly supports the conclusion that The New York Botanical Garden is an important and significant refugium or hotspot for local biodiversity.

Public gardens can help prevent detrimental effects of plant invasions by collecting and sharing data on taxa spreading from cultivation early in the invasion process, thereby acting as sentinels of plant invasion. Existing initiatives have called for public gardens to adopt measures preventing plant invasion, but it is unclear what actions individual gardens are implementing, as there is no formal mechanism for communicating their progress. This study used internal lists of escaping taxa from seven public gardens in the Midwestern United States and Canada to demonstrate how public gardens can collectively contribute data that is critical to assessing potential invasiveness. It also reveals methodological differences in how gardens develop their lists of escaping plants, leading to recommendations for standardization. Data pooled across gardens yielded 769 species spreading from cultivation at one or more gardens. Eight woody species were listed by all gardens despite not consistently being recognized as invasive by states and provinces containing the gardens; some species recorded by multiple gardens did not appear on any invasive lists. While it may be premature to call taxa escaping from cultivation at a few public gardens “invasive” or even “potentially invasive”, these plants should be monitored and evaluated with this information shared to facilitate stronger conclusions about risk. Thus, public gardens have a unique expertise in assisting invasive plant efforts as sentinels, particularly if challenges related to methodological inconsistencies and data sharing are suitably addressed, which is herein recommended through the adoption of a set of standardized guidelines.

The Brazilian Cerrado, the most biodiverse savanna globally with great importance for water and carbon conservation, faces the impacts of rapid and extensive land conversion, mainly for agricultural uses. The native Cerrado vegetation originally covered an area of 204 Mha however, 43% has been converted to human use. Pastures are the major land use category in Cerrado, covering 57 Mha, 28% of its area. Most of these pastures are underused and present some degree of degradation, representing an opportunity for restoration programs and agriculture expansion without further conversion of natural areas. The restoration of the Cerrado's degraded pastures is a source of recovery of ecosystem services, however, it might involve synergies and trade‐offs between ecosystem services and stakeholders. To evaluate potential trade‐offs, we modelled seven scenarios for prioritization for restoration, focusing on pasture areas on a biome scale. We considered biodiversity, water‐related ecosystem services, potential carbon stock and agriculture aptitude to understand the trade‐offs between each feature and the conflicts with agriculture. We also applied the same prioritization logic for one Cerrado ecoregion to understand the importance of planning on a finer scale. We identified important trade‐offs between the scenarios, especially with agriculture. The agriculture conflict scenario showed that 16 Mha of areas suitable to agriculture have also a high importance for restoration, representing a gain around 70% in ecosystem services and biodiversity. By refining the spatial scale of the prioritization process, we could also identify local conflicts and demands, which indicates the relevance of a local approach, allowing a more representative cover of the Cerrado's heterogeneity to minimize trade‐offs between different demands associated with restoration. Policy implications. The restoration of degraded lands is an international priority to mitigate climate change as well as protect the biodiversity. Our work provides a better understanding of the trade‐offs and conflicts involved in the restoration of the Cerrado, a megadiverse savanna with great importance in agriculture. This understanding is key to implementing public policies that enable large‐scale restoration projects while optimizing biodiversity conservation, ecosystem services provision and minimizing conflicts with agriculture.