Drought-time for Any Yahoola at the Angle of Repose

     The creek still flows.
     About as much as a leaky faucet.
     The Creek's water begins a hundred or so yards south of the Pond, weakly bubbling up among thick-growing water willow, pennywort, rabbit's foot grass, and algae.  From there, the Creek silently trickles from one small pool to the next, finally dripping into our main Pool.  I love it, though.
     I love every smell, every dried skin of algae draping sun-bleached stones, every mud-crack beside the shrunken Pond and Creek.  Like an aged lover, this thirsty little canyon remains as sweet to me as she was to me in our springtime.
     So, we are officially in the worst one-year drought the state of Texas has ever seen.
     This from College Station:

Preliminary reports from the National Climatic Data Center indicate that July 2011 was the warmest month ever recorded statewide for Texas, with data going back to 1895, Nielsen-Gammon reports [the Texas State Climatologist and professor of atmospheric sciences at Texas A&M University]. The average temperature of 87.2 degrees broke the previous record of 86.5 degrees set in 1998. The June average temperature of 85.2 was a record for that month and now ranks fifth warmest overall.
Rainfall totals were also unusually light across the state. The July monthly total of 0.72 inches ranks third driest, surpassed by the 0.69 inches recorded in both 1980 and 2000. This is the fifth consecutive month in which precipitation totals were among the 10 driest for that month, says the Texas A&M professor.
Among the other rainfall records set this month:  least year-to-date precipitation (6.53 inches; historical average 16.03 inches; previous record 9.36 inches in 1917);  driest consecutive 8, 9 and 10 months on record (7.25 inches 8.35 inches, and 9.17 inches respectively);  and driest 12 months ending in July (15.16 inches,  previous record 16.46 inches in 1925).
“These statistics rank the current drought as the most severe one-year drought ever for Texas,” Nielsen-Gammon explains. “Never before has so little rain been recorded prior to and during the primary growing season for crops, plants and warm-season grasses.”
Texas would need more than 4.5 inches of rain in the next two months to avoid breaking the 1956 record for driest 12 consecutive months, he adds. . . .
“The climate division that covers west-central Texas has received only 3.32 inches of rainfall since Nov.1,” says Nielsen-Gammon.  “That’s less than 21 percent of the historical average and less than half of the previous record, set in 1956.  Add in the record heat, and it’s just devastating.”

(http://tamunews.tamu.edu/2011/08/04/texas-drought-officially-the-worst-ever/)

     And now we heard yesterday that there's a fifty-fifty chance of a return to the La Nina weather phenomenon later in the year.




     Below is a view from the south end of the Pond where our pathetic little water gauge that was originally sunk into five or so inches of water now stands a fair distance from the retreating waters.  Last week we swam in the Pond, and it remains as refreshing as ever, actually.  The deep Spring still chills the water up around the spot on the west side where limestone dips down steeply.  
     In the photo one can just make out another water gauge placed at the shore last Sunday morning.  I extended the black plastic water pipe and electric cable another fifty feet since the submersible pump had ceased to be submersed.  (For a comparison, see the pictures from last March.)

How a Pond Travels North with the Summer Drought


     Here we show a lovely drought-yellow in a Chinaberry tree (Melia azedarach). 


     Such droughts are hard on some insects and beneficial to others.  Mosquitoes and ants take it hard.  And when dry conditions intensify, the antilions (Myrmeleon sp.) benefit to the extent that their inverted cones used as pit-fall traps become more effective. 

Antlion ( Myrmeleon sp.) Traps Under The Oak


     The antlion larvae begin construction of the pit by crawling backwards in a circle, lifting up the dry sand onto its back, then moving the sand to the top of its head with a front leg, where it finally flips away the sand with a series of quick snaps.  Eventually the circling works downward, creating in the process a pit whose walls remain about as steep as is possible.  This angle is referred to as the critical angle of repose, and for all granular materials such as rice, gravel, snow, ash, coffee beans, or sand, it's the steepest angle at which such things can be piled up.  But it works in reverse as well.  Some materials cave in or avalanche easier than others, depending on their density, the surface area of the individual pieces, and what's referred to as their coefficient of friction.  Finely pulverized alluvial sands in a central Texas drought behave differently than spent coffee grounds or piled human bodies.
     So when the pit is completed, the antlion buries itself at the bottom with its hollow-tubed jaws pointed upwards.  Then when the sad prey--ants, beetles, spiders, or whatever--fall into the trap, they are often prevented from escaping because of the avalanche-prone walls of their new-found hell.  Some will climb up and out to live another few short and miserable insect hours.  The rest may make it half way up the slippery slope, only to come sliding back down while the antlion flips sand out of the bottom of the hole, thus weakening the walls of the cone.  When the antlion is through sucking the innards out of the prey, it tosses the desiccated body back up.  Because it is able to draw out the wet guts of the ant or the beetle, this wonderful creature doesn't need to sip water from a creek or rain puddle, so a record drought may mean good times for the antlion.
     Myrmeleon (with 158 species) is the only genus of antlion in the United States that builds these sort of pit-fall traps.  Somewhere around 2000 species of antlion inhabit this globe.  Here in the South, they sometimes are called doodlebugs for their winding trails left in the sand as the larval form seeks out a place to design its famously inverted cone.  It's the adult stage that flies about in the evenings, resembling our damsel and dragon flies.  And most noteworthy as far as topics of meditation go, the antlion larvae lack an anus.  For the duration of the larval stage the insect stores up its . . . metabolic waste, waiting for the end of the pupal stage to poop.  Insects are interesting, but to our knowledge, the antlion is the only insect lacking an anus.  Meditation time over. 

     In the eastern parts of Asia, this insect goes by the name of "ant demon" and its trap as "ant-hell."  In Japanese, the word ari-jigoku (for the antlion's trap) also refers to a situation into which a person "falls" without hope of rescue.
     And yes, it's the Cherokee word for antlion that is yahoola.  
     Below is a short scene involving a small beetle narrowly escaping the grasp of the antlion on the morning of August 4 under The Oak:


Antlion, its Trap, and How a Beetle Lived to See Another Day



     But two turtles were not as fortunate as that beetle.  These remains were found just upstream from the Pool and on the east side of the Creek.



       I don't know what the odds are of finding two up-turned turtle carapaces within ten feet of one another, but the sight was a sad one.  I crossed the Creek and sat for half an hour on the shady west bank just above them.


     Below we have a unique plant among plants, the Sesbania herbacea, sometimes known as Hemp Sesbania, Bigpod Sesbania, Peaweed, Coffeeweed, Peatree, Danglepod, Colorado River hemp, or Indigo-weed.  I think (it should go without too much parenthetical interruption that everything I identify out here at The Creek may turn out to be something of a different order).  At first, I thought it might be another rattlebush (Sesbania drummondii) when it was young and still knee-high.  But now it has quickly proven to be its own, reaching now at least head-height.  The main stem is a glabrous green that will, I am told, completely die back next winter.  The "hemp" in some of its common names refers to the strong fibers within its main stem.  The fiber has been used to make fishing nets and was used extensively by Native Americans.




Bigpod Sesbania (Sesbania herbacea)








     Native to these Southern United States, Sesbania tends to grow in moist areas, like ours does here along the receding shoreline of the Pond and among the stones and sand of the creekside.  









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