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Abstract: To meet the demand for more and larger tallgrass prairie restorations, seed is frequently collected en-masse from remnant native plant populations. Overharvesting of seed may lead to population extinctions, [...]

The conversion of tallgrass prairie to agriculture has negatively affected provisioning of ecosystem services. Successful restoration of ecosystem services could depend on management decisions applied during revegetation projects. We examined the effects of three management decisions (seed mix design, planting time, and first‐year mowing) on targeted ecosystem services (erosion control, weed resistance, and pollinator resources). We tested three seed mixes of varying diversity and grass‐to‐forb seeding ratios: Economy mix (21 species, 3:1 grass:forb), Pollinator mix (38 species, 1:3), and Diversity mix (71 species, 1:1). We established plots at two planting times (dormant‐season and spring) with or without first‐year mowing. To assess ecosystem services, we measured stem density, canopy cover, and floral density and richness of sown species in the second year after planting. The Economy mix had the highest stem density and cover but lowest floral density and richness. The Pollinator mix had the lowest stem density and cover but highest floral density. The Diversity mix had comparable stem density and cover to the Economy mix and comparable floral density and richness to the Pollinator mix. Mowing accelerated native plant establishment in all seed mixes. Dormant‐season planting improved establishment of spring and fall forbs and favored cool‐season graminoids over warm‐season grasses. All three management decisions influenced ecosystem outcomes, and comparison to a previous study revealed these effects to be robust to variation in site and climatic conditions. We recommend a diverse, balanced seed mix design, first‐year mowing, and dormant‐season planting to improve multifunctionality of conservation projects. [ABSTRACT FROM AUTHOR]

In the Midwestern United States where the landscape has been largely converted from tallgrass prairie to row crops, thousands of private land parcels have been enrolled in federal pollinator habitat reconstruction programmes.To examine the outcome of pollinator habitat reconstruction, we randomly selected 19 sites that were in the third growing season post restoration and surveyed plant, floral and wild bee richness and abundance. Floral sources were divided into three categories: species from the seed mix (sown), species from the soil seed bank or surrounding landscape (unsown), and species that were likely unintentionally sown (contamination).Seventy‐two percent of captured bees were collected from sown flowers. The majority of oligolectic bees were Asteraceae specialists. Using linear regressions with bee abundance and richness as response variables and floral density and diversity as predictor variables, we showed that sown floral density was positively correlated with the total abundance and richness of bees collected from sown flowers, indicating that the selected pollinator friendly flowers provide support for wild bee communities. Conversely, total plant stem density or richness or the total floral density or richness was not significantly correlated with bee abundance or richness.The plant–pollinator network nestedness and modularity were positively correlated with the ratio of the unsown floral richness at each site, which suggests that the association between unsown flowers and wild bees can increase the long‐term stability of the plant‐pollinator network, even though the unsown species do not directly increase the bee abundance or richness. [ABSTRACT FROM AUTHOR]

Agricultural intensification continues to diminish many ecosystem services in the North American Corn Belt. Conservation programs may be able to combat these losses more efficiently by developing initiatives that attempt to balance multiple ecological benefits. In this study, we examine how seed mix design and first year management influence three ecosystem services commonly provided by tallgrass prairie reconstructions (erosion control, weed resistance, and pollinator resources). We established research plots with three seed mixes, with and without first year mowing. The grass‐dominated "Economy" mix had 21 species and a 3:1 grass‐to‐forb seeding ratio. The forb‐dominated "Pollinator" mix had 38 species and a 1:3 grass‐to‐forb seeding ratio. The grass:forb balanced "Diversity" mix, which was designed to resemble regional prairie remnants, had 71 species and a 1:1 grass‐to‐forb ratio. To assess ecosystem services, we measured native stem density, cover, inflorescence production, and floral richness from 2015 to 2018. The Economy mix had high native cover and stem density, but produced few inflorescences and had low floral richness. The Pollinator mix had high inflorescence production and floral richness, but also had high bare ground and weed cover. The Diversity mix had high inflorescence production and floral richness (comparable to the Pollinator mix) and high native cover and stem density (comparable to the Economy mix). First year mowing accelerated native plant establishment and inflorescence production, enhancing the provisioning of ecosystem services during the early stages of a reconstruction. Our results indicate that prairie reconstructions with thoughtfully designed seed mixes can effectively address multiple conservation challenges. [ABSTRACT FROM AUTHOR]