The sentences that use the word "foliage" correctly are:
- The swarm of insects damaged the foliage in the tomato fields. - correct
- Every year, thousands of tourists travel to New England to view the fall foliage. - correct
The first two sentences are incorrect uses of "foliage." In the context of cooking, "foliage" refers to plant leaves, which do not apply to potatoes, and the second sentence seems to be a misuse related to practicing with a sword.