Hi Ecologers, I'm planning a field study in which I need to achieve ~30cm precision in marking the locations of shrubs in a mountainous landscape in southern, coastal California. I have been told that differential GPS may be our solution. There's a lot of stuff out there on the web, so I'm a little overwhelmed with the apparent options. Also, when researching this a few years ago, I read about needing permission from the government for this kind of mapping precision. Is that true?
Can anybody provide a source of recommendations for DGPS units, caveats of their use, etc.? Help much appreciated. Cheers, tim --
