Physiognomy and Structure: Vegetation included in this alliance has a moderately sparse to moderately dense cover of broad-leaved deciduous shrubs 2 m tall. The sparse to moderately dense herbaceous layer is usually less than 1 m tall and dominated by graminoids. Some stands have herbaceous layers dominated by perennial forbs, but generally forb cover is sparse. Annuals are seasonally present.

Floristics: The sparse to moderately dense shrub layer is 1-2 m tall and is dominated by the cold-deciduous, broad-leaved shrub Cercocarpus montanus or the hybrid oak Quercus x pauciloba. Occasional trees, such as Juniperus spp., Pinus edulis, Pinus ponderosa, Pseudotsuga menziesii, or Quercus spp., may be scattered in some stands. Shrub cover is generally denser on northern aspects and increases with elevation. Lower elevation stands grade into shrub savannas with decreasing elevation. The herbaceous layer is sparse to moderately dense depending on the density of the shrub layer and soil moisture. It is dominated by perennial graminoids or forbs with annuals present seasonally. Associated species vary with location. In the western Great Plains, Artemisia frigida and Rhus trilobata are common woody species. The herbaceous layer is sparse to moderately dense and is dominated by the warm-season, perennial midgrass Bouteloua curtipendula. Achnatherum hymenoides (= Oryzopsis hymenoides), Aristida purpurea, Elymus elymoides, Hesperostipa comata (= Stipa comata), and Piptatheropsis micrantha (= Oryzopsis micrantha) may also be present. Common forbs are Artemisia ludoviciana, Hedeoma hispida, and Symphyotrichum oblongifolium (= Aster oblongifolius). Stands in the Rocky Mountain foothills are similar, but with the graminoid layer usually dominated by the cool-season, perennial mid grasses Bouteloua gracilis, Hesperostipa comata, or Hesperostipa neomexicana (= Stipa neomexicana). In addition to Artemisia frigida and Rhus trilobata, associated shrubs and dwarf-shrubs may include Purshia tridentata, Quercus gambelii, and Ribes cereum. Other associated species, such as Allium textile, Artemisia ludoviciana, Astragalus parryi, Bouteloua gracilis, Eriogonum umbellatum, Helianthus pumilus, and Poa spp., are common in the herbaceous layer. In the Chihuahuan Desert montane scrublands, the dominant species may be a different subspecies, Cercocarpus montanus var. paucidentatus. Associated shrubs and dwarf-shrubs include Madrean elements such as Agave parryi, Ceanothus greggii, Dasylirion leiophyllum, Dasylirion wheeleri, Ericameria laricifolia, Garrya flavescens, Garrya wrightii, Petrophytum caespitosum, Quercus grisea (shrub form), Quercus turbinella, Yucca baccata, and shrubby species of Opuntia, sometimes forming a mixed cold-deciduous/evergreen stand. Occasional trees such as Quercus arizonica, Quercus gambelii, and other Quercus spp. and conifers such as Juniperus deppeana may be present. The herbaceous layer is sparse on the very rocky sites to moderately dense, and usually is dominated by perennial grasses, including Aristida ternipes, Bothriochloa barbinodis, Bouteloua curtipendula, Bouteloua gracilis, Eragrostis intermedia, Koeleria macrantha, Lycurus phleoides, Muhlenbergia emersleyi, Muhlenbergia montana, and Muhlenbergia pauciflora. Forbs may be diverse and include Artemisia ludoviciana, Eriogonum jamesii, Hedeoma plicata, Heliomeris longifolia, Heliomeris multiflora, Mirabilis multiflora, and Viguiera dentata.

Dynamics:  Cercocarpus montanus is a dominant understory species in several woodland and forests dominated by Juniperus deppeana, Juniperus monosperma, Juniperus osteosperma, Juniperus scopulorum, Pinus edulis, Pinus ponderosa, Pseudotsuga menziesii, Quercus gambelii, Quercus grisea, and Quercus x pauciloba. Cercocarpus montanus stands often occur in the more xeric habitat below these woodland and forest stands. In xeric habitats studied by Greenwood and Brotherson (1978), Cercocarpus montanus sites had significantly more rock than the Pinus edulis and Juniperus osteosperma sites. Brotherson et al. (1984) suggested that stands are moisture-limited because stands on southern aspects were always higher in elevation than stands on northern aspects. However, Cercocarpus montanus did not typically occur with mesic shrubs such as Symphoricarpos oreophilus and Amelanchier alnifolia. There is often a broad Cercocarpus montanus shrub/herbaceous ecotone between these shrublands and grasslands. Ecological factors that control shrub densities such as fire and drought need more investigation. Unlike other species of Cercocarpus, Cercocarpus montanus is a fire-resistant species because it can resprout from the base after a fire has killed the top (Cronquist et al. 1997). In the southern portion of its range, Cercocarpus montanus functions as an evergreen shrub by retaining leaves during mild winters and losing them during cold winters (Dick-Peddie 1993). Cercocarpus montanus is preferred winter range browse for deer (Roughton 1966, 1972, Hoffman and Alexander 1987). Stands can also produce significant forage that can be utilized by grazing livestock provided the slopes are not too steep (Hoffman and Alexander 1987). More information is needed on the effects of livestock grazing and wildlife browsing on the structure and function of these shrublands.