Kenlguy: I know in Washington you can salvage the horns during Elk seasons - but you have to "tag" them.
Not sure what gives after a season?
I have done so (salvaged antlers/horns) in Montana several times now - including from archery wounded Elk, archery wounded Mule Deer, archery wounded Antelope and archery wounded Whitetails!
But I have done these more or less on the sly.
Last year an archery wounded Mule Deer had been slumping around in the fields adjacent to my home with an arrow through its neck for nearly two months. Numerous reports came to the local game warden detachment and they finally (after weeks of trying!) got close enough to this Buck Mule Deer to "dart" him and then remove the arrow.
We are seeing more and more Grizzly sign each year. Wife and I saw three Grizz in three separate spots in one day going over Beartooth Pass (not in a park but in public lands!).
It is time for a Grizzly season in Montana.
Hold into the wind
VarmintGuy