Help with Cyprus trees

Had 5 12' Leyland Cyprus trees planted last year. They're spaced about 10' apart from one another. They originally had an issue where they were turning brown and it turned out to be shock. During the late summer, early fall they started turning green and looked healthy. Now, they're turning brown again...I originally thought it was some kind of winter burn...but they're getting worse. One thing we did notice was a small (about 1/2" long) green worm on one of the leaves (can't find anymore). Could this be a problem? What are they and can they cause our trees to start browning? Any other ideas? (Oh, we live in NJ).