Halakhah for Chullin 272:49

And this commandment is practiced by males and females, Israelites and Levites, whether in front of the [Temple] or not in front of the [Temple]. But [it is practiced] only in the Land of Israel, and not outside of the Land; and like Rav Nachman bar Yitschak said in Chullin 136b in the chapter [entitled] Reishit HaGez, "The world acts like the three elders: Like Rabbi Eelayai in the first shearing, etc." - meaning to say that he exempted outside the Land, as it is found there. And one who transgresses it and did not give his first shearing to the priest - when he has shearing that is fit, according to the matter that we wrote - has nullified this positive commandment.