Collecting propolis is an arduous task. Yes, you can scrap propolis from a hive. However, you would get an inferior propolis since you will also get other unwanted bee products during the process.

Tricking the Bees

The best way to get pure propolis is by tricking the bees. What breeders normally do is by inserting small insets into the hives.

Bees will fill the insets with propolis because they are tricked into thinking that the inset is a part of their home that needs repair.

Link: Making your own propolis tincture