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Grasslands provide important provisioning services worldwide and their management has consequences for these services. Management intensification is a widespread land‐use change and has accelerated across North America to meet rising demands on productivity, yet its impact on the relationship between plant diversity and productivity is still unclear. Here, we investigated the relationship between plant diversity and grassland productivity across nine ecoclimatic domains of the continental United States. We also tested the effect of management intensification on diversity and productivity in four case studies.

We acquired remotely sensed gross primary productivity data (GPP, 1986–2018) and plant diversity data measured at different spatial scales (1, 10, 100, 400 m²), as well as climate variables including the Palmer drought index from two ecological networks. We used general linear mixed models to relate GPP to plant diversity across sites. For the case study analysis, we used linear mixed models to relate plant diversity to management intensity, and tested if the management intensity influenced the relationship between GPP (mean and temporal variation) and drought.

Across all sites, we observed positive relationships among species richness, productivity, and the temporal stability of mean annual biomass production. These relationships were not affected by the scale at which species richness was observed. In three out of the four case studies, we observed that management effects on species richness were only significant at broader scales (i.e., ≥10 m²) with no clear effect found at the commonly used 1‐m²quadrat scale. In one case study, species‐poor, intensively managed pastures presented the highest productivity but were more sensitive to dry conditions than less intensified pastures. However, in other case studies, we did not observe significant effects of management intensity on the magnitude or stability of productivity.

Generalization across studies may be difficult and require the development of intensification indices general enough to be applied across diverse management strategies in grazilands. Understanding how management intensification affects grassland productivity will inform the development of sustainable intensification strategies.

What are the rate, reversibility, and degree of symmetry in plant species compositional change in response to the addition and removal of cattle grazing in the shortgrass steppe? Specifically, how does the imposition and removal of grazing affect the abundance of perennial C₄shortgrasses and C₃midgrasses that are of primary importance for livestock production in the region?

Shortgrass steppe, northeastern Colorado, USA, in the North American Great Plains.

We evaluate rates and magnitude of basal cover change in newly ungrazed and newly grazed sites (established in 1991), relative to change in long‐term (grazed and ungrazed) comparison treatments (established in 1939) over 25 years. We also compare shifts in species basal cover in newly implemented treatments relative to baseline community composition measured at the start of the study.

Unlike the limited change observed in long‐term treatments between 1939 and 1991, we documented more rapid, reversible and largely symmetric effects of both the imposition and removal of grazing between 1992 and 2017. This was primarily due to differences in the rate of increase in basal cover of C₃midgrasses, litter, and bare ground. However, the rate and direction of change differed when assessed relative to continuously evaluated and (early‐treatment) baseline cover data.

Studies of plant community change in response to large‐herbivore grazing under varying ecological conditions and management regimes are needed to effectively guide the development and revision of state‐and‐transition models (STMs) for grassland managers, and to better detect and plan for dynamic ecological conditions. Effective adaptive management and STM development under a changing climate will recognize that effects of grazing and removal of grazing on shortgrass steppe can be reversible in a relatively symmetrical pattern, occurring within 6–16 years.