Four hundred fifty-two species, subspecies, and varieties of vascular plants have been identified at Scotts Bluff National Monument. The vegetation is divided into three major plant associations:
- the moderately dense mixed-grass prairie,
- the ponderosa pine/Rocky Mountain juniper/eastern red cedar forests, and
- the hardwood association along the floodplain of the North Platte River
Within these plant associations can be further found seven major habitat types: riverine woodland, coniferous woodland, mixed-grass prairie, riparian habitat associated with irrigation canals, pine-studded bluffs, shrub-dominated slopes, and badlands.
In 1995 twenty vegetation "mapping classes" were identified within the boundaries of the Monument in accordance with the Federal Geographic Data Committee's National Vegetation Classification Standard. A vegetation map was produced from this research. The mixed-grass prairie is the predominant vegetative cover of the Monument.