The Panhandle Plains are part of an ecological region of international significance. Scattered across the southern high plains of Texas, New Mexico, Kansas, Oklahoma and Colorado are more than 25,000 playa lakes -- havens for wildlife and people.
Playas are simple depressions in a prairie or plain where rainwater collects. In ancient times, bison used these wetlands as watering holes and wallows and the Native American tribes who followed the bison found good hunting, water and many edible plants nearby. Today, farmers often plant grain crops like wheat or corn around playas, which provide feeding, wintering and breeding areas for ducks, geese and other migratory birds.
Playas have an unpredictable and rapidly changing wet-dry cycle, which is essential to how they work — and provide benefits including groundwater recharge and wildlife habitat. Since playas depend on rainstorms to fill with water, it is not uncommon for a playa to be dry for long periods, years even, or to be wet several times during a growing season. No matter the amount of water — whether dry, moist, saturated, or flooded — playas are still working. In fact, without this natural cycle, they wouldn’t be as effective.
When dry, the clay soil in the playa basin contracts and forms large cracks. Then, when it rains, the first flush of water from surrounding uplands flows toward the playa. As water moves through the grasses surrounding the playa, sediment that may carry contaminants from farm fields is trapped and stopped from entering the playa. The water continues into the playa and into the cracks — beginning its journey to the underlying aquifer.
Once the clay becomes saturated, the cracks close, allowing the playa to hold water. Some of the water in the playa is used by plants or evaporates. Even when the clay basin is sealed, water continues its journey through the clay along roots and other small channels. When the playa is full, water also flows around the clay, through surrounding porous soil.
After the water is gone and the soil dries, prairie winds scour the playa basin, blowing out some of the sediment that has found its way into the playa. Over time, cracks reappear in the clay soil, and the playa awaits the next big storm when the cycle will repeat.
Plants and animals have adapted to this cycle and respond rapidly when playas become wet. Tiny seeds and eggs lay dormant in the soil, sometimes for several years, waiting for a heavy rainfall to germinate and hatch. The variable nature of playas enhances the plant diversity, which in turn leads to increased wildlife diversity. Birds and other prairie wildlife use wet playas for much-needed rest stops, water and food.Playas provide the most significant wetland habitats in the southern quarter of the Central Flyway for migrating and wintering birds. Up to two million ducks and hundreds of thousands of geese take winter refuge here. Shorebirds, wading birds, game birds, hawks and owls, and a variety of mammals also find food and shelter in playas.
At GZ just north of you is Playa TX_22843. To claim this cache – please send answers to the following questions via email or the Geocaching message application. If you don’t answer the questions your log will be deleted.
- Describe what you see to the north.
- Based on the description above what stage would you say this playa is in currently? Provide reasoning to support your selection.
- Dry
- Moist
- Saturated
- Flooded
- Based on what you are observing how long do you think it has been since it rained at this location?
- Optional – Take a picture of you/your group at GZ.
Source –Texas State Historical Association and Playa Lakes Joint Venture