Sampling

Sampling

April 21 and 25, 2013

We have been having much rain.  Up to this point, there had been a few warm days, but they were sandwiched by cold nights and mornings.  With at least some warm days, I thought it time to go down to Cottonwood Pond and do some sampling.  Did increasingly warmer temperatures ignite the development of more life in the pond?  What was happening around it?

First, I did some “sampling” around the pond.  Much was flourishing. 

New leaves had broken out and unfolded from many trees overhead and around the pond.

          

                                 American Hornbeam, a.k.a. Blue Beech, a.k.a. Muscle Tree
                                                          (leaves and flowers)

Catkins and strands of tree flowers were hanging from branches or fallen to the ground.

 Young Oak leaves and flowers (bottom), Maple flowers (top)

Willow leaves and catkins

Red-leaved Poison Ivy and other plants were beginning to fill the seep between the pond and the creek.

 Young Boxelder tree

Boxelder was leafing out from its green stems. 

  Many other plants were unfolding their leaves or flowers, among them Prairie Trillium, Cleavers, Stinging Nettle, Mayapples, Jewelweed.

Young Jewelweed plants with two sets of "true" leaves

There were some signs of animal life.  A small frog jumped into the water.

  Worms tunneled in the mud.  

Crawdads built their chimney homes in the mud.

  Raccoons left their footprints in the mud.

Spiders skittered across the leaf litter.

Squirrels left remains of acorns on a nearby rotten log.

The top of the root ball had become a veritable jungle of grasses, tree saplings, nettles, Elderberry and other plants.

Clearly, life was flourishing all around Cottonwood Pond.

But, was anything happening in the water?  Were there small macro-organisms taking hold yet?  Was anything working on breaking down the detritus that had settled on the bottom?

First, I measured the depth of the deepest part of the pond with the same broomstick/twine/rock method I had used last time (see the previous blog entry:  “Measuring Depth”).  Though there had been much rain, the depth was exactly the same as it was on March 27 (21 ½ inches).  In other words, the red twistie left on the twine from last time still landed at the water's surface.

I looked into the pond, comparing it to an earlier time, when we had consistently cold weather and the water had been very clear.

There was still some clarity.  I could see the sediment-covered detritus, though not in the deepest parts.  I could see various sticks and leaves.

But, the water had less clarity than it did earlier.  Also, I had noticed more green algal growth earlier in the year, during a brief bout of warm weather, on sticks, leaves, and on the fur of the drowned squirrel (there is no sign of the dead squirrel anymore, by the way).  On this day, things looked brown, with the exception of some green algae in the shallowest areas.

It was time to sample the water, and the mud.

I scooped up some of each in jars (much more than I needed, it turned out) and brought them up to the house.  

What have I concluded so far?

1.                  I now believe that the seep seeps from the pond to the creek, and that this helps regulate the pond level.  I think the pond is holding water well, due to the clay bottom and the thick layer of detritus on top of that.  The depth remained the same, even after heavy rains.  So, the overflow seeps from the corner of the pond to the creek, and is carried off by the creek.

(In the photo at the beginning of this blog entry - the pond and fallen Cottonwood tree seen from farther away - it is easier to see that the water must flow from the pond to the creek.)

2.                  We had not had a sufficient number of warm days in a row to consistently foster algal growth, as well as other pond life.

3.                  Since I do see frogs hop in, it is not an unwelcome or inhospitable place.

4.                  The recent heavy rains may have stirred things up enough to affect the clarity of the water.  This should also introduce more oxygen.