2. brave: splendid, beautiful.

4. sable: black, dark.

6. erst: formerly.

7. girded up: bound up.  —The picture below, by Vincent Van Gogh, shows wheat "girded up in sheaves."

8. Borne on the bier with white and bristly beard: —In this line the poet personifies sheaves carried on a harvest cart as a body carried on a bier.

9. of thy beauty do I question make,: i.e., I think over what is to become of your beauty.

10. wastes of time: things wasted or destroyed by time.

13. Time's scythe: Father Time is usually depicted with the scythe he uses to mow down people and everything else.

14. breed: offspring.  brave: defy