Photos of pruning...The before, the after and the Ugly...and weighing dormant pruning weights...sort of

Some further observations and takes on pruning

In the two photos immediately below one can see the same vine before and after pruning to the single high-wire training system. The idea is to leave two horizontal semi-permanent cordons with long spurs (4-5 buds) evenly spaced along each cordon. The previous cordons were removed and "new" cordons were tied down. Notice the horizontal "new" cordons are still technically canes that have been tied down. Over time, these will develop into semi-permanent cordons, from which spurs will arise and be pruned annually.

"The Before", un-pruned French-American hybrid vine at Los Lunas ASC

"The After", pruned French-American hybrid vine at Los Lunas, ASC

The next three photos depict the fact of grapevine anatomy. Unlike many perennial, temperate zone fruit crops (apple and peach) grapevines have no terminal bud. 

Grapevine cane with viable dormant buds. In the spring, new growth will arise from each of these buds. Each of these new shoots could have from 1-4 clusters of grapes. Later in the summer, these shoots will lignify (turn brown and form weathered bark) and will have newly formed buds for the subsequent season...and as Kurt Vonnegut  might say..."...and so it goes.."

In this photo, the end of the cane simply 'sloughed' off. The cane ends without a terminal bud. Also, notice the withered and desiccated appearance of this cane. It is not viable at this juncture and should be removed when the vine is pruned.

Finally, when making cuts that are larger than a dime...take time and inspect the exposed cut end. It should appear a slightly creamy green in color. That indicates it is likely free of infection from wood-rotting organisms.

The cut end of a cordon or small trunk. Notice the creamy, green color...it is indicative of healthy wood, likely free of wood rotting pathogens.

Which wood rotting disease is this? I cannot tell you. The organism would have to be isolated and identified by a pathologist or someone that has experience with these organisms. But the expression and result is similar within the grapevine...the discolored interior wood that is not functional and the compromised growth of spurs and canes that are associated with the diseased wood.  There are many wood rotting diseases...Botryosphaerria, Eutypa, Esca....to name a few. 

Link to scientific article on botryosphaeria dieback in grapevines and how to treat it surgically and how to dress the wounds

Finally, check out the photo below...the workers at the NMSU experimental vineyard at Fabian Garcia ASC in Las Cruces, are weighing pruning wood recently cut from the adjacent vines. The amount of one-year wood that was pruned from each vine will dictate how many buds/vine to leave to produce next year's crop.