We have repeatedly dealt with exactly the same situation you describe with
historic juniper tree cuts in Nevada, Utah and Wyoming.  Several years ago we
did an intensive study of seven antelope traps in northeastern Nevada for the
BLM.  We mapped the traps, described each in detail, photographed them and
took samples of juniper to try to get tree ring dates.  Unfortunately, Utah
Juniper is notoriously fickle for dating and we could not get any. There were
no Pinion trees associated with the traps.  Let me know if you would like
more information on our inventory.
 
This brings me to something you need to consider.  Juniper trees were
frequently used in Nevada, Utah and Wyoming for antelope trap construction up
into historic times.  We found some of the traps with axe cut juniper in the
vicinity that had been taken for use in the traps.  We also found trees  that
were torn off and burned off
for use in trap construction.  When Pinion is not available Juniper often
sufficed.
 
We have also found evidence, however, of juniper being cut in large numbers
in areas where we could not find signs of traps.  Whether the traps had been
destroyed since use, taken for firewood or whether the junipers were cut for
firewood or, possibly, fenceposts, we were not sure.  The firewood/fencepost
idea has considerable merit and I would consider that a significant
possibility if traps are not a possibility.
 
Mike Polk
Sagebrush Archaeological Consultants
Ogden, Utah