Saturday, September 11, 2010

Dry Prairie

Diversity in bedrock geology, soil type and topography brings about a great biological diversity in an area. Yesterday I was enjoying the tranquility of a shaded pool. By traveling a distance of only a few hundred feet, I’m now viewing a hot, parched grassland. Each area hosts its own unique suite of plant and animal life. The two areas are extremely different, but both represent healthy, vibrant, functioning ecosystems.

The Common Dropseed, Sporobolus vaginiflorus, is showing signs of severe drought stress. Some of the plants have turned completely brown and are probably past recovery, but the majority still show a central portion of healthy green leaves. Despite the lack of rain, there will be plenty of plants survive to produce seed for next year’s population.

People hate to see super dry ground. A sight such as this has many people wishing they could drag out the garden hose and soak the whole area. Changing the moisture regime on the site would certainly change its appearance. Regular irrigation could turn this into a lush, green landscape and most people would believe that they had really helped things out. The problem is that most of the plants now growing on the site would not survive to be a part of the new design.

Management of these sites requires that the manager have a clear concept of how the natural ecosystem should look. As with any type of habitat, there are certain plant and animal species associated with super dry locations. To successfully manage these areas, a good manager needs to avoid the natural bias against droughty sites with somewhat scraggly looking plants.

I enjoy visiting these dry areas. Judging from the number of old nests I discover each year, so do the box turtles. If box turtles consistently choose a site like this as providing the best chance of survival for their offspring, the super dry habitat must be a wonderful place.

4 comments:

  1. Hi Steve ...Quite a contrast from yesterdays post ..yes I did read it and found it very interesting. : }
    When I lived in Northern Me.we lived under a small mountain and there was places where water seemed to seep from nowhere trickling down over hugh rocks in the driest of summers... there was some bubbling springs in the Cedar woods.My grandfather had one he dug out and it provided them with the drinking water!! "oooh not today we wouldn't"
    Very dry looking there but next year it may have something different growing there!!
    I could see in the last photo what I think is the remainds of turtle egg shells ....I guess there is a reason for everything!!

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  2. You're right about the turtle egg shells, grammie g. The shells looked like the turtles had hatched out OK, but I could tell if the little turtles got away before some predator dug up the nest.

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  3. You think those red-cedars have recently invaded or are part of a longer term presence?

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  4. Ted- The larger cedars can clearly be seen on aerial photography from 1938, so they’ve got to be well over 100 years old. I’ve read historical accounts of this area that indicate plant cover consisted of shrubs and brush mixed with sparse grasses and forbs. Early records also refer to cedar being in the area.

    Size is not a reliable indicator of age with these cedars. I’ve cut 25 foot trees that were not more than 20 old. I‘ve also cut short trees that were quite old. I once cut a scraggly six foot cedar and with the help of magnification, counted at least 75 growth rings in its one inch diameter trunk.

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