Solum is a Khosla Ventures-backed (as in Vinod Khosla *) startup using tech for measurements in agriculture. Idea seems interesting. They seem to be only into conventional agriculture support, though.
* Vinod Khosla: google him.
But I wish Vinod would make some investments in large scale organic farming, given his avowed interest in cleantech / greentech. I'm sure he must know of its benefits vs. conventional agriculture that uses synthetic fertilizers and pesticides.