Sun State was hired to remove grass and replace with desert landscape. At the beginning of the project we questioned the project manager Mike Schneider on how the grass would be prevented from coming back, as he did not use a physical barrier. He assured us the chemicals would kills all grass, and they would verify by watering the grass was killed prior to placing rocks and new plants. The grass began growing through the rocks within a week of the rocks, and continues to do so. When contacted he sated this was because we did not hire a service? Sun State now claims the 6 month warranty has passed, so we will have to pay someone else to removed the rocks and kill the grass. Very disappointing, would not recommend for any project, as they do not stand behind their work.