German wine the best vineyards in Germany are steep vineyards overlooking rivers, where mechanisation is impossible and a lot of manual labour is needed to produce the wine. Since it can be difficult to get ripe grapes in such a northernly location as Germany, the sugar maturity of grapes (must weight) as measured by the Oechsle scale have played a great role in Germany. German vintners on average crop their vineyards quite high, with yields averaging around 64-99 hl/ha, a high figure in international comparison. "New" crossings used for low-quality white wine commonly yield 150-200 hl/ha, while quality-conscious producers who strive to
Wine Grapes and original work that is much more extensive in coverage, and also incorporates recent findings from ampelographic research, including DNA profiling of grape varieties. "Wine Grapes" include a catalog listing of 1,368 grape varieties from across the globe including 377 Italian, 204 French and 77 Portuguese wine grape varieties. Coverage includes a listing of synonyms as well as the genetic relationship between varieties derived from DNA analysis. According to Jancis Robinson and José Vouillamoz, "Wine Grapes" includes details about almost 300 previously unpublished relationship between different grape varieties including the extensive family tree of the Pinot grape that includes a