Turns out the beds were collected to be used as rebar for the dams that they built.  Another one was being constructed when the man died at 89.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/11376383@N00">Joseph</a> from Cabin On The Road, USA
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<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/umnak/6566423449/">Keys Ranch</a>