Orlo - עָרְלָה - is the Torah prohibition of eating fruit from trees less than 3 years old, as per last Wednesday's Halocho.
In the 4th year, the fruit is called נֶטַע רְבָעִי and needs to be "redeemed" by transferring its status onto a coin. The coin needs to be worth at least a "Peruta" (0.025 grams of pure silver; about 1½ US pennies at today's rate.)
In Israel one makes a Bracha when redeeming נֶטַע רְבָעִי:
One then says "I am redeeming the נֶטַע רְבָעִי into this coin".
The coin is then destroyed and disposed of.
Instead of a coin one can use fruit worth about 1½ pennies, which then needs to be destroyed.
After redeeming them, the נֶטַע רְבָעִי - the 4th year fruit - can be eaten, anywhere by anybody.
Sources: Kitzur Shulchan Aruch 173:2
Monday, 25 Menachem Av 5776