Most current conservation literature focuses on the preservation of hotspots of species diversity and endemism, as if the two were geographically synonymous. At landscape scales this may not be the case. We collected data from 367 1000‐m2 plots in the Grand Staircase–Escalante National Monument, Utah, USA, to show that: (1) the vast majority of plant species are locally rare; (2) species‐rich areas are generally in rare, mesic, or high‐elevation habitats such as aspen stands or riparian zones high in soil N and P; (3) endemic species (to the Colorado Plateau and the Monument) were generally found in relatively species‐rich, but low‐elevation, xeric vegetation type areas low in soil P; (4) unique species assemblages were found in areas moderately high in endemism and species richness; and (5) nonnative plant species were widely distributed, but more prevalent in species‐rich, mesic sites high in soil fertility or disturbed sites, and significantly less prevalent in plots with endemic species. We show that primary hotspots of species richness, high endemism, and unique species assemblages are not co‐located on the landscape. Hence, conservation strategies may have to consider a much broader concept of “hotspots” to adequately preserve native plant species and the processes that foster persistence.

We present an approach to quantitatively assess nonnative plant invasions at landscape scales from both habitat and species perspectives. Our case study included 34 nonnative species found in 142 plots (0.1 ha) in 14 vegetation types within the Grand Staircase-Escalante National Monument, Utah. A plot invasion index, based on nonnative species richness and cover, showed that only 16 of 142 plots were heavily invaded. A species invasive index, based on frequency, cover, and number of vegetation types invaded, showed that only 7 of 34 plant species were highly invasive. Multiple regressions using habitat characteristics (moisture index, elevation, soil P, native species richness, maximum crust development class, bare ground, and rock) explained 60% of variation in nonnative species richness and 46% of variation in nonnative species cover. Three mesic habitats (aspen, wet meadow, and perennial riparian types) were particularly invaded (31 of 34 nonnative species studied were found in these types). Species-specific logistic regression models for the 7 most invasive species correctly predicted occurrence 89% of the time on average (from 80% for Bromus tectorum, a habitat generalist, to 93% for Tamarix spp., a habitat specialist). Even with such a modest sampling intensity (<0.1% of the landscape), this multiscale sampling scheme was effective at evaluating habitat vulnerability to invasion and the occurrence of the 7 most invasive nonnative species. This approach could be applied in other natural areas to develop strategies to document invasive species and invaded habitats.

We investigated the use of prairie dog towns by cattle (Bos taurus) on the shortgrass steppe of northeastern Colorado by conducting surveys of cattle and vegetation from June to August 1999. Cattle presence and behavior were recorded 3 times a week during driving surveys of 15 black-tailed prairie dog (Cynomys ludovicianus) towns. A subset of 3 pastures with prairie dog towns was intensively surveyed twice weekly wherein the habitat and activity of a randomly chosen focal animal was recorded every 6 minutes for 3.5 hours. Bite and step counts of other individuals were recorded for 5-minute intervals. Vegetation height and cover data were collected monthly on each of 6 habitats.Results from driving surveys and intensively surveyed pastures were similar; cattle neither significantly preferred nor avoided prairie dog towns. Bare ground cover on prairie dog towns did not significantly differ from most other habitats, but vegetation on prairie dog towns was significantly shorter on (mean = 6.7 cm) than that off (mean = 11.9 cm) prairie dog towns.Nevertheless, foraging observations indicated that there was no significant difference between cattle foraging rates on swales (70.9 bites/min) and prairie dog towns (69.5 bites/min). Thus, cattle on the shortgrass steppe appear to use prairie dog towns in proportion to their availability and, while there, they graze as intensively as they do on habitats not inhabited by prairie dogs.

We investigated the use of prairie dog towns by cattle (Bos taurus) on the shortgrass steppe of northeastern Colorado by conducting surveys of cattle and vegetation from June to August 1999. Cattle presence and behavior were recorded 3 times a week during driving surveys of 15 black-tailed prairie dog (Cynomys ludovicianus) towns. A subset of 3 pastures with prairie dog towns was intensively surveyed twice weekly wherein the habitat and activity of a randomly chosen focal animal was recorded every 6 minutes for 3.5 hours. Bite and step counts of other individuals were recorded for 5-minute intervals. Vegetation height and cover data were collected monthly on each of 6 habitats.Results from driving surveys and intensively surveyed pastures were similar; cattle neither significantly preferred nor avoided prairie dog towns. Bare ground cover on prairie dog towns did not significantly differ from most other habitats, but vegetation on prairie dog towns was significantly shorter on (mean = 6.7 cm) than that off (mean = 11.9 cm) prairie dog towns.Nevertheless, foraging observations indicated that there was no significant difference between cattle foraging rates on swales (70.9 bites/min) and prairie dog towns (69.5 bites/min). Thus, cattle on the shortgrass steppe appear to use prairie dog towns in proportion to their availability and, while there, they graze as intensively as they do on habitats not inhabited by prairie dogs.

We briefly reviewed the literature on habitat matching in invading non-native plant species. Then we hypothesized that the richness and cover of native annual and perennial plant species integrate complex local information of vegetation and soils that would help to predict invasion success by similarly adapted non-native plant species. We tested these Ôlife-history habitat matchingÕ relationships in 603 0.1-ha plots, including 294 plots in Colorado, which were relatively high for the cover of native perennial plant species, and for 309 0.1-ha plots in southern Utah, which were relatively high in the cover of native annual plant species. We found strong positive relationships between the richness and foliar cover for both native and non-native species, whether they were annual or perennial species (0.34 > r 2 < 0.53; P < 0.0001). We also found significant positive relationships between the cover of native annual species at a site and the richness (r 2 = 0.13; P < 0.0001) and the foliar cover (r 2 = 0.06; P < 0.0001) of non-native annual species. The proportion of non-native annual species in the flora of a plot also increased significantly with the foliar cover of native annual species. Conversely, the richness and cover of non-native annual species were significantly negatively associated with the foliar cover of native perennial species (r 2 = 0.05 and 0.06, respectively; P < 0.0001). The cover of non-native annual or perennial species was not significantly correlated with soil texture variables, %N, or %C. We conclude that there may be a high degree of life-history habitat matching by non-native annual species in these study sites. Information on native annual and perennial species richness and cover may help characterize the complex soils, climate, and disturbance environment in which similarly adapted non-native plant species establish and gain foliar cover.