While searching for George Lepp and his articles on the web (see previous post) I found an interesting article with a technique about using flash in nature and landscape photography. It's called "Flash Magic" - Interview by Rob Sheppard. And while you are there, don't forget to look at other articles on this website. Such as "Learning from a Master" by Moose Peterson.

UPDATE:
Here is another article on flash in nature and landscape photography - Smart Flash Outdoors by Galen Rowell.