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Managed low‐severity surface fires are frequently implemented in efforts to restore disturbance processes to forests of North America; although the effects of managed fire on forest structure are well‐studied, few studies investigate whether these disturbances cascade to impact pollinator communities.We analysed bee‐habitat relationships in fire‐treated (1‐ and 3‐years post‐treatment) and non‐treated ponderosa pine stands in Colorado to test wild bee population responses.Observed bee richness and α‐diversity were highest in stands 1‐year post‐fire and had more Anthophora, Bombus, Osmia and Lasioglossum spp. in comparison to 3‐year post‐fire and non‐treated stands. Bee functional groups were responsive to treatments, with more below‐ground nesting taxa present in stands 3 years post‐fire.Floral richness was the highest mid‐growing season (June, July) and within 1‐year post‐fire stands.A model analysing the effects of foraging and nesting habitat variation on bee assemblages indicated positive association between floral richness and bee α‐diversity, but negative relationships with stand basal area. Nesting habitat was not associated with variation in bee assemblages.We conclude that managed fire has positive short‐term effects on bee biodiversity that are likely mediated by floral richness. However, these effects were not detectable by 3 years post‐treatment in the southern Rocky Mountain region. [ABSTRACT FROM AUTHOR]

In response to large, severe wildfires in historically fire-adapted forests in the western US, policy initiatives, such as the USDA Forest Service’s Collaborative Forest Landscape Restoration Program (CFLRP), seek to increase the pace and scale of ecological restoration. One required component of this program is collaborative adaptive management, in which monitoring data are used to iteratively evaluate and improve future management actions. Here, we assess the success of seven CFLRP treatments, implemented on 2,300 ha during the first three years of the Colorado Front Range Landscape Restoration Initiative (LRI) at achieving desired forest structure by comparing pre- and post-treatment conditions. We also compare post-treatment conditions with reconstructions of historical (ca. 1860) forest conditions to contextualize the magnitude of treatment effects. Restoration projects moved stands toward desired conditions by reducing basal area, tree density, and canopy cover and increasing average tree diameter, large gap cover, and abundance of small- to medium-sized tree groups. Post-treatment stands were similar to historical stands with respect to basal area of ponderosa pine; however, they had higher total tree density and fewer gaps than historical reference conditions, suggesting that restoration prescriptions may be improved with increased flexibility for density reduction of Douglas-fir and increased gap creation. This examination of early CFLRP treatment outcomes as they relate to desired conditions informs potential areas of adjustments to future treatments and provides baseline data to evaluate the evolution of treatments over the program’s lifespan. We also identify and discuss several scientific, social, and logistical constraints to large-scale restoration success and make several recommendations to improve restoration outcomes. [ABSTRACT FROM AUTHOR]