After passing on Saruman's postBody to Gandalf, Radagast headed out to the boondocks to act as "control" over his friendly herds and flocks of secret agents that were sent out to spy on the doings of the enemies.
Besides sending secret reports to Gandalf, he also sent them to Elrond in Rivendell, Galadriel in Lothlorien, the Beornings on the plain between the Great River and Mirkwood, and to the peoples of Dale and the Lonely Mountain.
Using Radagast's reports, these free peoples of northern Middle-earth were able to coordinate their effort against the enemy forces; thus doing their part in the last major battles of the' War of the Rings'.
The reason you didn't read about this in the books, was that these clandestine operations were highly classified and weren't released to the general public until after the death of King Elessar.
Okay, I made most of that up, but it may have happened that way. :elfbiggrin:
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