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.

Seed supply often limits the size and scope of restoration projects that require active revegetation. To meet demand from more and larger tallgrass prairie restoration projects in the Great Plains, U.S.A., seed is wild-harvested-collected from remnant habitats-using agricultural combine harvesters. We investigated the potential impacts of wild-harvest by comparing prairie remnants of northwestern Minnesota that varied in their histories of harvest frequency but were otherwise similar. We asked:(1) Do wild-harvested prairies differ in species composition from unharvested prairies? (2) If so, can life history traits be used to predict the response of prairie communities to wild-harvest? We conducted a retrospective study of 17 prairies harvested for seed frequently (annually/biennially), infrequently (2-3 times), or not at all. We sampled vegetation at 45 points within each site, recording all species present within 0.25 m 2 quadrats. To address the first question, we used non-metric multidimensional scaling and Mantel tests, followed by analysis of variance contrasts to identify any species less likely to occur on frequently harvested sites ("harvest-negative"). For the second question, we used logistic regression to test whether lifespan, clonality, and seed production predicted harvest-negative species. Plant community composition in frequently harvested prairies differed from that of infrequently or unharvested prairies. Fourteen species, generally short-lived and non-clonal, were classified as harvest-negative. Our results suggest that frequent wild-harvest disrupts reproduction of species relying on seed, and that life history traits may provide a basis for predicting a species' response to wild-harvest.

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.

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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, but these risks are not well studied. Species’ reproductive strategies may provide a basis for risk assessment. We assessed extinction risks associated with seed harvest for grassland plant species with different reproductive strategies (clonal vs. non-clonal). Using stage-based matrix models, we projected the extinction risk for two clonal and four non-clonal prairie species subjected to five harvest scenarios: (i) no harvest, (ii and iii) annual harvest at low/high intensity (50% and 75% seeds removed), and (iv and v) triennial harvest at low/high intensity. We compared the magnitude of growth or decline (λ) and mean extinction risk among populations during a 25-year modeling period. Non-clonal species were robust to triennial and low-intensity harvest, but susceptible to decreases in population growth (λ) up to 0.5 and elevated extinction risks up to 95% with high intensity annual harvest. Clonal species were unaffected by seed harvest, owing to a compensatory effect of vegetative propagation on growth rates. To maintain populations of non-clonal species in remnant grasslands, high intensity annual harvest should be avoided.