White wine the death knell of northern viticulture. The vine disappeared from northern Germany and Baden, and the maximum altitude for viticulture descended to 220 metres. Hans-Jürgen Otto noted that: "all the vineyards suffered and decreased in area". In England the vine also disappeared. The less early vineyards preferred to select white varieties of grapes because, even if unripe, white grapes allowed wine that was a little sour to still be consumable, while red grapes do not give enough colour and green tannins make the wine bitter. The interruption of the fermentation by a cold winter led to the discovery of the
Buff (colour) such a material. Unless bleached or dyed, paper products, such as Manila paper, tend to be buff. Buff envelopes are used extensively in commercial mailings. Buff paper is sometimes favoured by artists seeking a neutral background colour for drawings, especially those featuring the colour white. Buff domesticated animals and plants have been created, including dogs, cats, and poultry. The word "buff" is used in written standards of several breeds, and some, such as the Buff turkey, are specifically named "buff". In 16th- and 17th-century European cultures, buff waistcoats ("vests" in American English), were considered proper casual wear. In the 17th