By "salt the earth" I assume he is refering to practice of salting the farms of the nations you are fighting with in war because the salt prevents them from beening able to grow food. So in this context Carol is preventing his idea from having any chance of working by her comments.
Yes, please interrupt us from working. As much as you want, actually. For hour and days on end, till the CEO comes along and wonder what the &#€% is going on.