The oak makes potentially nutritious seeds (acorns) that contain very bitter-tasting tannins. If we could breed the tannin out of acorns, they might become a delicacy.
Why do you suppose we have failed to domesticate oaks?
There is one very simple reason why we have not yet figured out how to domesticate oaks. Consider the plants that biotechnologists have been able to manipulate (corn, tomato, wheat, etc.). Now, consider the ...
Oak domestication is debated.