they act as miniature greenhouses for the fledgling trees. gela tetrauli learned these methods for combating soil erosion in germany. two months before, he and a few other farmers from georgia paid a visit to some farmers in central germany. >> we're quite a bit behind, agriculturally. the germans are at least ten years ahead of us. and when we catch up with the germans, then they'll be ten more years ahead of us. it's just like the mountains. once you've climbed the first one, the next one is already there to greet you. >> here on a farm near frankfurt, the georgian farmers learned about modern methods of soil conservation. hans kellner is an experienced farmer, and had a lot to teach them. >> look at the field here. there's plenty of empty space, where no wheat is growing. just like right here, or over here. you don't need to have your entire surface covered in wheat. the important thing is having sturdy plants, like this here. >> modern cultivation methods and careful tending help preserve the soil. hans kellner also doesn't use a traditio