In the extreme westernmost sub-region of Texas, which include the Toyah Basin and the Stockton Plateau eco-regions, the Great Plains are bordered to the west by the Basin and Range Region.

Of the five ecoregion of the Great Plains in Texas, the Toyah basin is the one that is the westernmost part of the Texas Great Plains and the ecoregion is located adjacent to the same ecoregion in New Mexico.

The Toyah basin in both New Mexico and Texas, is a broad valley on the east side of Pecos River, and this region, in relatively recent times, has become important for many agricultural products as a result of irrigation from the Pecos river.

Also, another important economic activity is afforded by local oil fields in what has come to be called the Permian basin oil field.

The Toyah basin is considered by some to be part of the larger Chihuahuan Desert ecoregion, which includes alluvial fans, internally drained basins and river valleys, primarily below 3500 feet in elevation. Some of the other basins included within this ecoregion are the Hueco basin, Salt basin, and Presidio basin. These low elevation basins represent the hottest and most arid habitats in this two state region (Texas, New Mexico) with less than 12 inches of annual rain.

These basin floors have alkaline soils and areas of salt flats, dunes and windblown sand. The typical desert grasses and shrubs grow in this area and include: creosotebuse, tarbush, fourwing saltbush, blackbrush, gyp grama, alkali sacaton and all of which have the need to endure extremee temperature variations, low moisture availability, and extreme high evaporation rate.

Located adjacent to the Chihuahuan desert, east of the Guadalupe Mountains and Davis Mountains, northwest of the Edwards Plateau and just north of the Stockton Plateau, the Toyah Basin is a broad, flat remnant of an old sea floor that occupied the region as recently as the early Quaternary period.

Due to this region being within close proximity of the Chihuahuan Desert, all of all of this region is very hot and dry.

Most of the little rainfall that occurs is in the high elevations of the mountains, but occasionally, during the winter or early spring, there will come a rain shower in other locations.

The Toyah alluvial sedimentary basin is a north by northeast trending trough over 1000 feet in depth, created by dissolution of underlying Permian oil evaporates.

Monahans Sandhills State Park

Monahans Sandhills State Park is noted for the presence of sand dunes up to 70 feet high. Although desert-like, the Monahans Sandhills are not considered to be a desert, but are a part of a semi-arid ecosystem characterized by the presence of both groundwater and nutrient-poor windblown sand, an area that has an average annual rainfall of 12.3 inches.

However, the Chihuahuan desert to both the south and west is adjacent to these sandhills and because of the proximity of the Chihuahuan desert, the sandhills are located on the dry side of the Climate Divide and thus are in an area considered to be a very dry region.

Considered by some to be a separate ecoregion, this area is named after the Shin oak bush that stabilizes sandy areas subject to wind erosion and includes sand hills, dunes and flat sandy areas. This sand was likely blown out of the Pecos River Basin and stoped by the Llano Estacado located at the western edge of the New Mexico Tablelands Ecoregion.

The Shin oak (Quercus havardii) is a local climax shrub, an unusual type of oak tree which because of local conditions often achieves full growth of only 4 feet in height. Most of the biomass of a Shin oak exists in the form of a lengthy root system reaching down to groundwater.

If a Monahans sand dune has become stabilized and has stopped blowing about in the wind, that is often because a small grove of Shin oaks have stabilized the dune with their extensive root systems.

Both sagebrush and several prairie grasses, (dropseed, sand bluestem, big sandreed) may create a continuous plant cover in portions of the Shinnery, the cover is often absent or sparse in the dune areas.

The Shinnery sands are habitat for the lesser prairie chicken, a species that is in serious decline. The shinnery shrubs offer cover and shade for nesting while the shin oak acorns are a staple food source. The decline of the prairie chicken is connected the the loss of the shinnery to other uses.

Despite the sterility of the landscape, various rodents are relatively common, and several packs of Sandhills coyotes feed upon them.

Awake, rise, dress in my fall blues, drive to the w-mart for coffee and then leave town driving west on IH 20 for about fifty miles to Monahans Sandhills State Park for a hot shower. I drive into the park, acquire a day pass and drive to the shower house, grab my shower bag and walk into the building. I then turn on the hot water and I have to jump back because it is so hot. Wow, I have never seen water this hot in a state park shower before. I will be coming back here each time I pass this way.

I then take photos of the park, and dunes after which I leave out and drive back the fifty miles to Midland where I stop at the w-mart.