Nathan Wreyford <<nathan.wreyford>>
writes:

I was pleasantly ignorant of these until seeing them every where
this year. I never thought of the panhandle as having wetlands.

Https://tpwd.texas.gov/landwater/land/habitats/high_plains/wetlands/playa.phtml

Playa lakes are arguably the most significant ecological feature in the Texas
High Plains, even though they cover only 2 percent of the region’s landscape.
Playas are shallow, circular-shaped wetlands that are primarily filled by
rainfall, although some playas found in cropland settings may also receive water
from irrigation runoff. Playas average slightly more than 15 acres in size.
Although larger playas may exceed 800 acres, most (around 87 percent) are
smaller than 30 acres. Approximately 19,300 playas are found in the Texas High
Plains, giving us the highest density of playas in North America.

Compared to other wetlands, playas go through frequent, unpredictable, wet/dry
cycles. In wet years they support the production of annual plants, such as
smartweeds and millets. These plants produce a tremendous crop of seeds that are
favored by dabbling ducks and other seed eating birds. The wet/dry nature of
playas, along with their high plant production, means they produce an abundance
of invertebrates. This productivity makes playas havens for birds and other
wildlife throughout the year.

Once the subject of much debate, mounting evidence points to playa lakes as a
critical recharge source for the Ogallala aquifer. Playas filter and recharge as
much as 95 percent of the water collected in the southern portion of the
aquifer. Recharge occurs both through playa basins and along the perimeter (or
annual rings) of playas. Recharge occurring through playa basins flows downward
through large cracks in the clay lining. These cracks eventually swell shut and
become impermeable as the clay absorbs water following a rain. Recharge
occurring along playa perimeters takes place after rainfall events leave
flood-water standing outside the clay-lined basins. Because of their role in
recharging the Ogallala, the conservation of playas is as important to humans as
it is to wildlife.