How's this for a corny ASCII visual?  (section through ha-ha)
 
____
    \
-----:
 [+] |
     |__
 [+] |--|                         @(=)' --cow  (no bull)
_____|..|........             .....^.^........
////////////////^.           .^\\\\\\\\\\\\\\\
/////////////////^.         .^\\\\\\\\\\\\\\\\
//////////////////^.   |   .^\\\\\\\\\\\\\\\\\\
////////////////////^..|..^\\\\\\\\\\\\\\\\\\\\
///////////////////////////////////////////////
 
Cows and sheep can't ruin your lawn and no unsightly fences, or
in otherwords, no blatantly man-made objects to spoil your view
of the beautiful "natural" landscape.
 
My dictionary defines "ha-ha" as follows:  "Also haw-haw.  A
moat, walled ditch, or hedge sunk in the ground to serve as a
fence without impairing the view or scenic appeal; sunken
fence.  [French haha, from haha!, interjection used to express
surprise, presumably because the fence is an unexpected
obstacle.]"
 
They served a purely aesthetic function in picturesque
landscaping of the late 18th and early 19th centuries.  I
suppose it's possible that some groups may have used such
structures in defensive works (no doubt with a palisade of
sharpened stakes).
 
Marty Perdue
--staying up too late--
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