Edwards Plateau Limestone Savanna and Woodland

These relatively closed woodlands are very common on uplands on limestone in the Edwards Plateau and adjacent ecoregions. Juniperus ashei (Ashe juniper) is the clear dominant in the canopy and a conspicuous component of the shrub layer as well. Juniperus virginiana (eastern redcedar) may be present in the canopy to the northeast, while Juniperus pinchotii (redberry juniper) may be present to the west. Occurrences containing thick stands of juniper are sometimes referred to as "cedar breaks." Some sites mapped as this type may actually be dominated by Pinus remota (paper-shell pinyon), though Juniperus ashei (Ashe juniper) or Juniperus pinchotii (redberry juniper) are often present in the canopy as well. Pinyon woodlands tend to occur on relatively xeric sites and have a sparse herbaceous layer with species such as Bouteloua curtipendula (sideoats grama), Hilaria belangeri (curlymesquite), Erioneuron pilosum (hairy tridens), and others. Quercus fusiformis (plateau live oak) is often a significant component in the canopy, and other species such as Quercus buckleyi (Texas oak), Quercus sinuata var. breviloba (white shin oak), Quercus vaseyana (Vasey shin oak), Quercus laceyi (Lacey oak), Ulmus crassifolia (cedar elm), and Celtis spp. (hackberry) may also be common. The shrub layer may be dense and dominated by Juniperus ashei (Ashe juniper), but Mahonia trifoliolata (agarito), Diospyros texana (Texas persimmon), Prosopis glandulosa (honey mesquite), and other species may be present. Dense canopy cover often leads to a sparse to nearly absent herbaceous layer, sometimes with only Carex planostachys (cedar sedge) present.

Distribution Map

Photos

Public Land Occurrence

• Abilene State Park Area: Texas Parks & Wildlife Department
• Amistad National Recreation Area: US National Park Service
• Balcones Canyonlands National Wildlife Refuge: U. S. Fish and Wildlife Service
• Barton Creek Habitat Preserve: The Nature Conservancy
• Colorado Bend State Park: Texas Parks & Wildlife Department
• Devil's River State Natural Area: Texas Parks & Wildlife Department
• Friedrich Wilderness Park: City of San Antonio
• Garner State Park Area: Texas Parks & Wildlife Department
• Government Canyon State Natural Area: Texas Parks & Wildlife Department
• Hill Country State Natural Area: Texas Parks & Wildlife Department
• Kerr Wildlife Management Area: Texas Parks & Wildlife Department
• Kickapoo Cavern State Park Area: Texas Parks & Wildlife Department
• Pedernales Falls State Park: Texas Parks & Wildlife Department
• Possum Kingdom State Park Area: Texas Parks & Wildlife Department
• Schnabel Park: City of San Antonio

These relatively closed woodlands are common throughout the Edwards Plateau and adjacent ecoregions on limestone. Quercus fusiformis (plateau live oak) dominates the overstory, however other species such as Quercus sinuata var. breviloba (white shin oak), Ulmus crassifolia (cedar elm), Quercus buckleyi (Texas oak), Celtis spp. (hackberry), Quercus laceyi (Lacey oak), Quercus stellata (post oak), and Quercus vaseyana (Vasey shin oak) may also be present to common. Juniperus ashei (Ashe juniper) and/or Juniperus pinchotii (redberry juniper) may be present in the canopy and shrub layer, but are not typically dominant. The shrub layer is generally patchy and may include species such as Diospyros texana (Texas persimmon), Prosopis glandulosa (honey mesquite), Mahonia trifoliolata (agarito), Opuntia engelmannii (prickly pear), and Opuntia leptocaulis (tasajillo), as well as small individuals of the overstory species. Cover of the herbaceous layer may be high, but sparse if woody cover is high, with species including Schizachyrium scoparium (little bluestem), Bouteloua spp. (grama), Nassella leucotricha (Texas wintergrass), Aristida spp. (threeawn), and Carex planostachys (cedar sedge). Fires in this system tend to remove shrub species (especially Juniperus ashei (Ashe juniper)), but the overstory typically remains intact. Openings between mottes are typically grass dominated with the same species that occur as understory components in the woodlands.

Distribution Map

Photos

Public Land Occurrence

• Amistad National Recreation Area: US National Park Service
• Colorado Bend State Park: Texas Parks & Wildlife Department
• Devil's River State Natural Area: Texas Parks & Wildlife Department
• Devil’s Sinkhole State Natural Area: Texas Parks & Wildlife Department
• Garner State Park Area: Texas Parks & Wildlife Department
• Government Canyon State Natural Area: Texas Parks & Wildlife Department
• Guadalupe River State Park: Texas Parks & Wildlife Department
• Hill Country State Natural Area: Texas Parks & Wildlife Department
• Honey Creek State Natural Area: Texas Parks & Wildlife Department
• Kerr Wildlife Management Area: Texas Parks & Wildlife Department
• Kickapoo Cavern State Park Area: Texas Parks & Wildlife Department
• Mason Mountain Wildlife Management Area: Texas Parks & Wildlife Department
• Pedernales Falls State Park: Texas Parks & Wildlife Department

These woodlands are intermediate between those strongly dominated by the evergreen components Juniperus ashei (Ashe juniper) and Quercus fusiformis (plateau live oak) and those dominated by deciduous components, particularly oaks such as Quercus buckleyi (Texas Oak), Quercus sinuata var. breviloba (white shin oak), and Quercus laceyi (Lacey oak). Other deciduous overstory species that may be present include Ulmus crassifolia (cedar elm) and Celtis spp. (hackberry). The understory of these sites is similar to that of the related woodlands with shrub species such as Diospyros texana (Texas persimmon), Mahonia trifoliolata (agarito), Sophora secundiflora (Texas mountain-laurel), Prosopis glandulosa (honey mesquite), and Opuntia engelmannii (prickly pear), and relatively sparse herbaceous layer typically dominated by graminoid species common to the surrounding upland sites such as Bothriochloa ischaemum var. songarica (King Ranch bluestem), Schizachyrium scoparium (little bluestem), Bothriochloa laguroides ssp. torreyana (silver bluestem), Dichanthelium spp. (rosette grass), Bouteloua spp. (grama), Nassella leucotricha (Texas wintergrass) and others.

Distribution Map

Photos

Public Land Occurrence

• Abilene State Park Area: Texas Parks & Wildlife Department
• Amistad National Recreation Area: US National Park Service
• Balcones Canyonlands National Wildlife Refuge: U. S. Fish and Wildlife Service
• Barton Creek Greenbelt: City of Austin
• Barton Creek Habitat Preserve: The Nature Conservancy
• Devil's River State Natural Area: Texas Parks & Wildlife Department
• Friedrich Wilderness Park: City of San Antonio
• Government Canyon State Natural Area: Texas Parks & Wildlife Department
• Guadalupe River State Park: Texas Parks & Wildlife Department
• Honey Creek State Natural Area: Texas Parks & Wildlife Department
• Kickapoo Cavern State Park Area: Texas Parks & Wildlife Department
• McAllister Park: City of San Antonio
• Meridian State Park: Texas Parks & Wildlife Department
• Olmos Basin Park: City of San Antonio
• Pedernales Falls State Park: Texas Parks & Wildlife Department

While Quercus buckleyi (Texas oak), Celtis spp. (hackberries), and Ulmus crassifolia (cedar elm) are significant elements of the canopy of nearby slope forests and woodlands, they may also dominate upland sites. Other deciduous species, such as Quercus sinuata var. breviloba (white shin oak), Celtis laevigata (sugar hackberry), Prosopis glandulosa (mesquite), and Quercus stellata (post oak), may also occupy the canopy, with lesser amounts of evergreen components, such as Quercus fusiformis (live oak) and Juniperus ashei (Ashe juniper), present. These sites with dominant deciduous canopies on upland Ecological Sites (such as Low Stony Hill, Shallow, and Adobe) are less commonly encountered than woodlands dominated by some mix of an evergreen canopy.

Distribution Map

Photos

Public Land Occurrence

• Abilene State Park Area: Texas Parks & Wildlife Department
• Amistad National Recreation Area: US National Park Service
• Balcones Canyonlands National Wildlife Refuge: U. S. Fish and Wildlife Service
• Belton Lake Recreation Area: US Army Corps of Engineers
• Devil's River State Natural Area: Texas Parks & Wildlife Department
• Friedrich Wilderness Park: City of San Antonio
• Garner State Park Area: Texas Parks & Wildlife Department
• Government Canyon State Natural Area: Texas Parks & Wildlife Department
• Kerr Wildlife Management Area: Texas Parks & Wildlife Department
• Kickapoo Cavern State Park Area: Texas Parks & Wildlife Department
• Mason Mountain Wildlife Management Area: Texas Parks & Wildlife Department
• McAllister Park: City of San Antonio
• Stillhouse Hollow Lake Recreation Area: US Army Corps of Engineers

These woodlands and mottes tend to occur on Redland Ecological Sites, but may also be found on sandy benches. On the Edwards Plateau, Redland sites are often associated with cherty or siliceous members of limestone formations such as Edwards Limestone, Tanyard, Gorman, and Honeycut Formations. Sandy Cretaceous formations (such as Hensell Sand) may also harbor this vegetation type. These situations provide slightly more acidic conditions relative to the surrounding landscape. The overstory tends to be open and dominated by Quercus stellata (post oak), though Quercus marilandica (blackjack oak), Quercus fusiformis (plateau live oak), Ulmus crassifolia (cedar elm), Juniperus ashei (Ashe juniper), and Quercus buckleyi (Texas oak) may also be present. The shrub layer is patchy and may contain small individuals of the canopy species as well as other species. The herbaceous layer is often dominated by Schizachyrium scoparium (little bluestem), Nassella leucotricha (Texas wintergrass), Bouteloua curtipendula (sideoats grama), and other species, but may be dominated by the non-native Bothriochloa ischaemum var. songarica (King Ranch bluestem). In areas of transition to the Crosstimbers (such as in the Limestone Cut Plain and Carbonate Cross Timbers), it may be difficult to distinguish this system from Crosstimbers Oak Forest and Woodland.

Distribution Map

Photos

Public Land Occurrence

• Balcones Canyonlands National Wildlife Refuge: U. S. Fish and Wildlife Service
• Colorado Bend State Park: Texas Parks & Wildlife Department
• Honey Creek State Natural Area: Texas Parks & Wildlife Department
• Kerr Wildlife Management Area: Texas Parks & Wildlife Department
• Mason Mountain Wildlife Management Area: Texas Parks & Wildlife Department
• Pedernales Falls State Park: Texas Parks & Wildlife Department

Uplands of the Edwards Plateau are frequently described as a mosaic of woodlands, shrublands, and grasslands. Areas with reduced woody cover may occupy sites of considerable size, depending on the land use history, management, and fire history. While these sites have sometimes been referred to as prairies, they are more appropriately considered a part of the savanna mosaic. Grasslands in areas transitioning to regions with a prairie matrix (such as the northwestern transitions to shortgrass prairie, northern transitions to mixedgrass prairie, and northeastern and eastern transitions to tallgrass prairie), may closely resemble and be difficult to distinguish from these prairie types. Schizachyrium scoparium (little bluestem), Aristida purpurea (purple threeawn), Nassella leucotricha (Texas wintergrass), and Bouteloua curtipendula (sideoats grama) are common dominants on these sites, but Bothriochloa ischaemum var. songarica (King Ranch bluestem) and/or Cynodon dactylon (bermudagrass) frequently dominate or are significant components. Numerous other grass species, including Aristida spp. (threeawn), Bothriochloa barbinodis (cane bluestem), Bothriochloa laguroides ssp. torreyana (silver bluestem), Sorghastrum nutans (Indiangrass), Bouteloua hirsuta var. pectinata (tall grama), Bouteloua trifida (red grama), Bouteloua rigidiseta (Texas grama), Bouteloua hirsuta (hairy grama), Erioneuron pilosum (fluffgrass), Hilaria belangeri (curly mesquite), and many others may be present or dominate these sites. Open, gentle slopes underlain by Glen Rose Limestone often maintain grasslands that are often dominated by Bouteloua pectinata (tall grama) and Muhlenbergia reverchonii (seep muhly). Sites under heavy, continuous grazing, or sites with thin or xeric soils tend to be dominated by shortgrass species such as Bouteloua dactyloides (buffalograss), Hilaria belangeri (curly mesquite), or Erioneuron pilosum (fluffgrass). Numerous forb species are also present in the herbaceous layer. Woody cover constitutes less than 25% of the canopy and is made up of various species including, but not limited to, Prosopis glandulosa (mesquite), Juniperus ashei (Ashe juniper), Mahonia trifoliolata (agarito), Quercus sinuata var. breviloba (white shin oak), Quercus fusiformis (plateau live oak), Diospyros texana (Texas persimmon), Ziziphus obtusifolia (lotebush), and/or Sophora secundiflora (Texas mountain-laurel).

Distribution Map

Photos

Public Land Occurrence

• Abilene State Park Area: Texas Parks & Wildlife Department
• Balcones Canyonlands National Wildlife Refuge: U. S. Fish and Wildlife Service
• Fort Richardson State Park and Historical Site: Texas Parks & Wildlife Department
• Garner State Park Area: Texas Parks & Wildlife Department
• Government Canyon State Natural Area: Texas Parks & Wildlife Department
• Guadalupe River State Park: Texas Parks & Wildlife Department
• Hill Country State Natural Area: Texas Parks & Wildlife Department
• Honey Creek State Natural Area: Texas Parks & Wildlife Department
• Kerr Wildlife Management Area: Texas Parks & Wildlife Department
• Kickapoo Cavern State Park Area: Texas Parks & Wildlife Department
• Mason Mountain Wildlife Management Area: Texas Parks & Wildlife Department
• Possum Kingdom State Park Area: Texas Parks & Wildlife Department