Physiognomy and Structure: Vegetation included in this alliance has an open to moderately dense tree canopy (5-25% cover) that is typically 3-8 m tall. Stands are either solely dominated by evergreen needle-leaved trees, or may be codominated by broad-leaved or scale-leaved evergreen trees. A moderate herbaceous layer (>25% cover) dominated by perennial graminoids is typically present. Perennial forbs may be scattered. Annual forbs and grasses may be seasonally present.

Floristics: These savannas and open woodlands have widely spaced mature juniper trees (5-25% cover) and moderate to high cover of perennial graminoids (>25% cover). Shrubs are absent or have low cover when compared to the abundant graminoid layer. The presence of Madrean junipers Juniperus coahuilensis or Juniperus deppeana is diagnostic. Juniperus deppeana has a broader range than this Madrean alliance, but is a diagnostic tree species of this wooded savanna alliance. Juniperus monosperma trees may be present to sole canopy dominant when diagnostic Madrean understory species such as Muhlenbergia pauciflora, Muhlenbergia setifolia, and Schizachyrium cirratum are present. Other characteristic graminoids may include Aristida spp., Bothriochloa barbinodis, Bouteloua chondrosioides, Bouteloua curtipendula, Bouteloua eriopoda, Bouteloua gracilis, Eragrostis intermedia, Lycurus sp., Muhlenbergia emersleyi, Muhlenbergia porteri, Muhlenbergia torreyi, Poa fendleriana, Schizachyrium sanguineum var. hirtiflorum, Schizachyrium scoparium, and on clay soils, Hilaria belangeri. Scattered perennial forbs include species of Eriogonum, Machaeranthera, and Sphaeralcea. Annual grasses and forbs such as Bromus and Erodium are seasonally present.

Dynamics:  Juniperus deppeana is a slow-growing, drought-tolerant, long-lived tree that will resprout if cut or top-killed by fire (Wright et al. 1973, Lamb 1975, Muldavin et al. 1998c). Although fire rarely kills Juniperus deppeana, it will reduce the size of the tree and allow grass to grow under it (Wright 1972). Juniperus coahuilensis will also resprout after being cut or burned which allows quick recovery after fires (Kral 1993). However, Juniperus monosperma is non-sprouting and may be killed by fire (Wright et al. 1979). Large juniper trees do not generally burn unless fine fuels, such as tumbleweeds, have accumulated beneath the tree to provide ladder fuels for the fire to reach the crown. Closed-canopy stands rarely burn because they typically do not have enough understory or wind to carry a fire. Altered fire regimes, fence post cutting, and improper grazing by livestock have significant impacts on the quality of sites. Grazing by livestock can modify the fire regime by removing the fine fuels that carry fire. Fire, livestock grazing, and trampling by recreationalists and vehicles disturb cryptogamic soil crusts that help maintain soil structure, reduce soil erosion, provide habitat for plants and preserve biological diversity (Ladyman and Muldavin 1996). More study is needed to understand and manage these woodlands ecologically.