Emerald Riesling, one of the earliest of the vine varieties developed at the University of California (see davis) by Dr H. P. Olmo to emerge in varietal (white) wine. It is a cross of a variety labelled Muscadelle (but not true muscadelle) and Grenache and had its heyday in the late 1960s and early 1970s before slumping towards oblivion. Just 152 ha/375 acres remained in 2011, mainly in the very south of the san joaquin valley, and nearly all of the grapes disappear into generic blends. It has also been tried in south africa and makes off-dry wine in israel.
