The wild bunch.

Growing across a few open-topped, gravel-filled steps next to Vinoland's crush-pad is a wild grapevine (and some blackberries).  The vine is not really wild, as it most likely originated from a seed of a cultivated variety that was processed in Vinoland and somehow managed to germinate in an untended corner of the property. 
So what is it?  Well, the berries are spherical, green and tiny - 7mm, 8mm tops - and oh so very tasty.  The vine has had no measurable amount of water since the last proper rain (in the spring), so that could account for the berries being so small.  The clusters are cylindrical with shoulders, but that alone doesn't help to identify this vine.  Looking at the cluster did however narrow the ID down to three varieties; Chenin blanc, Semillon or Viognier - all of which have made at least one appearance in Vinoland (along with Chardonnay, Gewürztraminer, Marsanne, Orange Muscat and Pinot grigio).  No, for that I needed to take a closer look at the vine's leaves.  An ampelography, observations of leaf characteristics, is the only reliable way to properly identify a grapevine, especially one that has been water-stressed all season.  And sure enough, the mystery vine's leaf gave the game away; "...mostly 3-lobed with wide U-shaped petiolar sinus and reduced lateral sinuses; medium-length, sharp teeth; slightly bullate surface; light to moderately tufted hair on lower surface." (Wine Grape Varieties in California, UCANR Publication 3419).  Drum roll...Vinoland now has a volunteer, self-rooted Viognier vine.
No pruning, no sulphur, no water, no love.  This grapevine is just doing it's thing.  I love grapevines.