Antonyms for the word "treasure-troves" are not common in the English language. However, some possibilities include "barren lands," "barren fields," "deserts," "unexciting yards," "bare plots," "unproductive areas," "sterile regions," "lifeless spaces," or "vacant lots." These words signify places or spaces that lack valuable finds or hidden treasures. Although these antonyms may not have the same elegance as "treasure-troves," they are still useful in many situations. For instance, if you need to describe a location that has no hidden gems, you can use these words to paint a more vivid picture in your audience's mind.