That definitely looks to me like it's sticking out of the ground rather than resting on top of it!
I'd let the brightest highlights continue down a little bit more, maybe a pixel, if not all the way to the bottom. There are only three things that would prevent those highlights from reaching the bottom:
1. The lightsource (or the light-coloured object being reflected) is small and there's no more of it to reflect. That doesn't seem to be the case here.
2. The surface there isn't vertical, it goes inward. Like on an upside down hat :] That's not the case here either.
3. Something is blocking the highlight in that spot. In this case, that could be the dirt, however it wouldn't block that much, since the light source is coming from above the dirt and the dirt is small. It would at most block a pixel of highlight on the bottom.