diff --git a/Makefile b/Makefile
index 60487cc17adbdf0bf4d7fdb8ebfc975a1bb223a0..16afa08c3e197ae94d56a9f2ff8a2a86bc5ffe6a 100644
--- a/Makefile
+++ b/Makefile
@@ -15,7 +15,7 @@ all : $(OUT_MARKUP) $(OUT_OTHERS)
 
 prepare : $(OUT)
 	git fetch origin public
-	git worktree add $(OUT) public
+	git worktree add --track -B public $(OUT) origin/public
 
 wipe :
 	find $(OUT) -mindepth 1 -not -name '.git' -delete