Yes, they should come off as soon as they reach full curl. Cut as low as you can, then snip off the blossom ends because they are tough. Whole scapes will keep in the fridge for more than a week. We cut them into half inch piece and blanch and freeze them. Only hardnecks make scapes, it's like an extra vegetable. Delicious.

I second that. I always cut off my scapes because they're so tasty. Still get big bulbs anyway. They're really good stir-fried.

Thanks PLANATUS and NEOHIPPI, for your response. I have used leek scapes before. So I sould cut them before they get tough. what will become of the blossom end if I leave the scape untouched? I will leave one or two to find out.

if you leave the scape untouched, it will form a cluster of bulbils at the top. size varies with variety from small pea shaped to about the size of a wheat berry. the larger bulbils you can plant. the first year they usually form a single clove called a round. plant the round, and you will get a full size bulb of garlic the following year. the tiny bulbils take 3 years to form a full size bulb.
planting bulbils is a relatively quick way of increasing your garlic supply if you have a variety that you really like.

keith