Quitting time.

All the grapevines in Vinoland have pretty much shut down.  In fact, driving through the valley, there aren't many leaves on vines to be seen anywhere - except for some apparently virused vines that are hanging onto their bright red leaves a little longer.  This particular node that I photographed, although it's a very nice node - nice bud, nice abscission scar, nice tendril - seems to be having a little trouble shutting down, as some of the tissue on this vine has not fully lignified.  The wood of this shoot is still slightly green and soft.  This vine also has quite a few petioles that are still clinging onto their shoot for dear life having abscised their individual leaf blades (the petiole usually separates with the leaf blade still attached).
Now I'm not an expert, and if there is anyone out there that can enlighten me further please feel free to chime in, but I do know that poor lignification of grapevine tissue can be due to a number of factors, among them; virus infection, water stress, deficiency of nutrients (as well as an oversupply) and differing levels of phytohormones such as auxins and cytokinins.
It's just one grapevine so I'm not unduly worried, but it does give me pause for thought.  And something else to research about the life and growing habits of these fascinating plants.

A blotch on the landscape.

Just a quick post.  It's Monday night and I'm tired.
The Oakville Winegrowers held a meeting, late this afternoon, at TWWIAGE.  On the agenda was a presentation by Dr. James Stamp on Grapevine Red Blotch-associated Virus.  Commonly referred to simply as Red Blotch, this is a fairly new grapevine virus (unexplained disease symptoms were first categorised in 2007, in Oakville) that may have dire economic ramifications for commercial growers and wineries.  And to be quite honest, nobody really knows much of anything about this virus.  For example, it is thought that possible vectors of the disease are leafhoppers, or whiteflies, but the research is ongoing.
The photograph shows a sampling of the handiwork of some of the participating wineries.  Yes, the meeting had a rather serious tone, but that didn't stop the attendees from tasting the goods.  It was quite a who's who of Oakville.  I just hope that none of these vineyards are infected with Red Blotch already.  Yikes.
I'll be attending a seminar on Red Blotch later in the month, so hopefully I'll learn a little bit more about this disease.  Stay tuned.

All stuffed up.

I might have been on holiday, but the grapevines haven't.  There is a lot to do right now out in the vineyard;  suckering the trunks, thinning out the heads and stuffing the shoots into the trellis wires. When I have gently coaxed all the shoots under the first trellis wire the vines will be all stuffed up, just like me, as I returned from Blighty with a nasty virus that has been totally enfeebling.
The weather was pretty nice in Vinoland whilst I was away, glorious by English standards.  The vines all look healthy, verdant and vigorous - and virus free, unlike me.

The essence of senescence.

Things are starting to look a lot different around here.  Things are looking more...yellow. It's a good job that I think yellow is a very nice, happy colour because every vineyard around here is not so green anymore.  The grapevines have given up their crop for this vintage and are now shutting down for their long winter nap, a process called senescence.  A grape leaf lives for approximately 150 days and so the first to give up the ghost and fall to the ground is usually the first one that grew in the spring.  The vine, however, first removes any goodies it can from the leaves and stores what it can in it's root system.  This way it is assured a kick start in the spring when the ground begins to warm up again.  The correct colour sequence is green, then yellow and finally brown...and down, not the autumnal colours depicted on postcards all over the Napa Valley.  Red leaves mean the plant is virused and will eventually die.  I must confess that I love to see the horrified look on visitors faces when I tell them that.  My grandmother would have said that the 'divil' was in me.