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Australian temperate grasslands are among its most threatened plant communities. In agricultural landscapes, major barriers to their recovery are high soil nutrient levels that favour the growth of exotic pasture and other non-native species, high standing weed biomass creating fierce aboveground competition, and rich weed seed and bud banks providing dense emergent seedling competition. Therefore, the return of grasslands to arable landscapes through restoration must rely on overcoming these challenges, ideally by reducing soil nutrients and mitigating the effects of weeds. This study demonstrates the effectiveness of topsoil removal for restoring diverse native grassy communities by direct seeding on sites with a legacy of elevated soil nutrients and competitive exotic vegetation. Conversely, it showed that repeated shallow cultivation (four times over 12 months) to stimulate weed emergence, followed each time by herbicide application, failed to achieve this outcome, at least in the short term (three years). Grassy community restoration is imperative in Australia, but importantly, it must utilise restoration protocols that are as effective as possible so that limited time, money, and resources are not wasted. In this light, the technique of topsoil manipulation may take us one step closer to achieving this goal in agricultural locations, where their loss is most pronounced. [ABSTRACT FROM AUTHOR]

Summary: This study was conducted across twelve agricultural locations in south‐western Victoria, Australia, encompassing a range of soil types and climatic conditions. It investigated the addition of an open layer of coarse organic pine wood chip mulch (~70% surface cover) directly following direct seeding of native grassland species. The intent was to mimic positive effects of naturally occurring organic surface litter (which are typically depleted in such settings) on seedling emergence and establishment. Findings revealed negative results in that the use of an open layer of coarse pine chip mulch failed to improve native establishment at 12‐months or to moderate soil temperature and moisture extremes in comparison to non‐mulched plots. This outcome suggests the effectiveness of open surface mulches under the scenario of direct seeding may be highly site context, mulch‐type, and application approach dependent. In situations where such mulch applications are not likely to be beneficial, significant costs relating to their purchase and application could be avoided. [ABSTRACT FROM AUTHOR]

Summary: This innovative roadside restoration project aimed to replace two historic non‐endemic block tree plantings with diverse native grassland. A secondary goal was to reintroduce populations of threatened species as part of the restorations (Button Wrinklewort; Clover Glycine; Hoary Sunray; and the Yam Daisy) Glycine latrobeana; Leucochrysum albicans subspr; i. The project applied what were at the time newly developed site preparation, direct‐seeding and seed production approaches designed to facilitate these outcomes. The long‐term success of these restorations (13 years) provides compelling evidence that it is feasible to restore high‐quality, low‐biomass, species‐rich native grasslands on previously exotic‐dominated roadsides. By doing so, they demonstrate that road networks offer broad canvases for restoration action and should in the future be used to create extensive native linear corridors, displaying high native biodiversity, visual and functional attributes. [ABSTRACT FROM AUTHOR]

Many small‐scale projects in Australia suggest that ground‐layer elements of ecosystems can be restored, but scaling up of grassland and grassy understorey restoration has not occurred to date. Paul Gibson‐Roy recently travelled through the USA, where well‐developed markets for restoration have created a large, financially viable native‐herbaceous seed production and restoration sector. Here, he shares his observations, which show how much about the USA situation can be a model and inspiration for Australian grassy ecosystem restoration. [ABSTRACT FROM AUTHOR]

Past intensive land use complicates the successful restoration of oligotrophic species-rich grassland types. One of the major bottlenecks are the elevated nutrient levels due to fertilization, especially residual phosphorus (P). Aiming to deplete nutrients, managers often reintroduce traditional haymaking management, sometimes combined with grazing. Here, we evaluate whether this technique restores the abiotic and biotic boundary conditions for restoration of Nardus grassland. Seven grasslands were selected in Flanders, Belgium, which had elevated nutrient levels after the cessation of intensive agriculture 16-24 years ago, and which have been mown and grazed since. We compared soil and vegetation data of these postfertilization grasslands with 34 well-developed oligotrophic Nardus grasslands. Mowing and grazing did not cause community composition to resemble that of Nardus grassland. Furthermore, bioavailable P-concentrations were significantly higher in the postfertilization grasslands and P-limitation was not obtained. Restoring P-poor soil conditions through continued mowing and grazing management would take at least decades. Phosphorus-mining can shorten the restoration time by increased P-removal. Given our results, we propose a decision framework to aid planners and managers in their choice of interventions. Cost-effective efforts for restoration should be well-prepared, including measurements of important initial soil characteristics. This allows for an evaluation of 'distance to target' and the selection of an effective restoration technique. These techniques may involve cutting the mowing tradition, and utilizing P-mining or topsoil removal instead. [ABSTRACT FROM AUTHOR]

A marriage of ecology with agronomy is proving successful in restoring diverse herbaceous layers - to the extent that some reconstructed grasslands on ex-agricultural land and rural roadsides have been found eligible for federal protection as threatened ecological communities. Can lessons from this improve our management and expansion of grassy ecosystems more broadly? [ABSTRACT FROM AUTHOR]

Fifteen native and common exotic herbaceous species from four functional groups (C4 grass, C3 grass, chamaephyte and hemicryptophyte) occurring within remnant and revegetated grassland and grassy woodlands were sampled for evidence of structures associated with functioning arbuscular mycorrhizal fungi ( AMF) from across a broad geographical range of central and south-western Victoria, Australia. Revegetated communities had been established on ex-agricultural land by direct seeding. They included sites that had been kept fallow with herbicide for up to 3 years prior to seeding and those from which topsoil had been removed (scalped) to a depth of 100 mm prior to seeding. Structures associated with AMF (external and internal aseptate hyphae, arbuscules and vesicles) were observed in root samples from all native and exotic species, regardless of site history (remnant or revegetated; fallowed or scalped). These findings indicate that AMF are ubiquitous in the herbaceous flora of this region (native and exotic), even in situations where sites had been intensively disturbed prior to revegetation treatment. However, while there was evidence of AMF in all revegetated communities, only sites which had been scalped prior to direct seeding supported species-rich native herbaceous communities. [ABSTRACT FROM AUTHOR]

Both reservation of small remnants and ecological restoration of degraded areas will be crucial if the Victorian Western (Basalt) Plains grassland community is to be conserved in the long term. This study examined the potential of direct seeding as a technique for grassland restoration by recording the initial establishment and subsequent recruitment success of 64 (predominantly perennial) grassland species direct sown onto a constructed site. Forty-three (67%) of the sown species emerged and established during the 2-year study and a further three species were recorded in subsequent years. In the second year, 32 species increased their number either through seedling or vegetative recruitment and 30 species dispersed beyond their original sown plot. Seed size was not correlated with field emergence but life form did influence initial field success for some groups. The finding that many species are able to establish and recruit under the study conditions supports the need for further investigation of direct seeding in the restoration of grassland communities. [ABSTRACT FROM AUTHOR]