Comments on: Precision Viticulture Controversy

By: Jeff Harries

Jeff Harries — Fri, 20 Apr 2007 08:15:28 +0000

Here is a very interesting link FYI.

http://www.usyd.edu.au/su/agric/acpa/people/james/Thesis/PhD_Taylor_2004.pdf

By: Jeff Harries

Jeff Harries — Fri, 20 Apr 2007 08:12:32 +0000

PV enables you to understand the extent of variability in your vineyard and begin to discover the reasons behind that variability. Walking around your vineyard is necessary but by itself is not sufficient to understand what is going on and why.
Just one component of variability is yield. Within block yield variability is often 4 times or more (ie 2-8 tons). That has been the experience of Bramley in Australia and it was my experience in British Columbia. Knowing what the variability is, what is causing it, and how to manipulate those factors is incredibly important. It is important to quality, costs, and to revenues. People often throw away valuable grapes in the mistaken belief it will improve quality when it may make the quality worse. Or they do some other expensive change or procedure without knowing what is really going on .
It is important to note that quality parameters also vary widely across single blocks.
As far as expense goes, it is cheaper to do it now than it was when I first did it ten years ago. GPS units are much cheaper now and so is software. I used MapInfo and Vertical Mapper which at the time was about $3000. I don’t know what that software would cost now. I know that Manifold software now does far more for less than $400.
I didn’t use satellite images, only baseline air photos. We set up Sentinal Vines throughout the vineyard, geo-located them on the surface of the Earth and then collected information at each location. The data included soil data, slope, variety, clone, soil parameters including macro and micro-nutrients, etc. Then each year we collected growing year data such as pruning wt./meter of trellis, inter-node length, bunches per cane, berries per bunch, bunch wt., berry wt, petiole nutrient data (N, K, P, Cu, Mg, Mn, etc.), pH, T.A., brix, Tons/Acre, etc. The surfaces made from these data points show surprising relationships between various inputs, outputs, and data types. The facts, relationships, opportunities, and conclusions that appear out of the data are not, for the most part observable from walking through the vineyard. And even fewer are that way between vintages. There is simply far too much data for our minds to observe, know, manage, and correlate without using a GIS. It is simply impossible. From my experience without a GIS you couldn’t do it for more than a thousand plants (

By: Morgan Twain-Peterson

Morgan Twain-Peterson — Mon, 16 Apr 2007 23:16:08 +0000

sorry for the grammatical deviance of the first sentence above. also, let me know when you are free to show me around up at your place.

By: Morgan Twain-Peterson

Morgan Twain-Peterson — Mon, 16 Apr 2007 23:15:07 +0000

Josh, your second to last mini-graph of the previous comment are interesting ones. I have been thinking about this and asking a few viticulturalists about their take on PV and it seems that many of them believe that when PV is used it is often used too late to make a large difference, or is necessary to make up for lack of forethought in vineyard layout. As we all know the costly replanting of high-vigour AXR rootstock (atleast high-vigour until its roots began to be munched on) allowed vineyard owners to replant using new and better rootstocks, clones, and trellising systems, and better adapting a vineyard to its site. That said, often times little is done to research a site effectively prior to planting. The “blocks” are placed down in a vineyard in their normal four sided shapes with little attention paid to soil and temperature difference. The result being that for the life of the vineyard one has to contend more and more with inner-block variation. And though good on the ground time and using such tools as PV aid in abetting inner-block fluctuation it still is a costly pain in the ass. So, if you ever get to do pre-planting contracts (which a lot of Pinot producers are doing these days) PV could really help out lay down the groundwork and make the next fifty years of vineyard maintenance a but easier.

Now, I realize that my earlier comments came across as more luddite than I intended. I, too, am of the feeling that whatever can aid in quality is worth it when one is able to sell grapes for the ultra-premium market. My point was just that many, many, wonderful wines have been made without it. That multiple generations and multiple hundreds of hours spent interracting with a piece of land can tell you as much as you need to know to make intensely enjoyable wine. And that, I believe, is all of our goals.

By: Josh

Josh — Sun, 15 Apr 2007 06:42:47 +0000

Bradley,

Thanks! Nice to have at least one guy in my corner.

Jefe,

I appreciate your point, but it oversimplifies a bit. Not all 10 acre vineyards are created equal.

Even a small 10 acre vineyard can quickly become too complicated for paper *if variation is high*. Now, granted a valley floor block with zero slope doesn’t pose that much of a problem, assuming that soil and water holding capacity are uniform.

But when you introduce changing slopes, multiple aspects and different soil types, gophers, virus pressure, fungus, nematodes and weather into the equation I defy anyone to capture the required information onto paper in anything close to an adequate way.

The only thing that can possibly tame the variation I’ve described is time and experience. And I’m thinking *a lot* of time, on the order of decades.

It sucks but I just don’t have the time wait. The baby’s hungry!

Plus I don’t think that conventional methods are anywhere near as accurate as an NDVI map, and research seems to bear this out. If I’m able to differentially manage even 2 tons of grapes from a lower quality tier into a higher quality one, the hassle and cost were more than worth it. And I think the return will be much more than 2 tons.

Not to mention that the sucker is portable so I can use it on strange new vineyards that I’ll /lease/contract out with in the future.

I know talk is cheap though, so I guess I’ll just have to try it to find out for sure. I’ll keep you posted.

By: El Jefe

El Jefe — Sun, 15 Apr 2007 06:09:44 +0000

If I have only 10 bills to pay each month (oh how I wish!) I can do this on paper with a simple register and do a good job. If I have 1000 bills to pay, perhaps bringing a little tech to bear would be a good idea.

Similarly, at 10 acres perhaps I can track my measurements and observations on paper, perhaps by row. AT 1000 acres WOW wouldn’t a GIS be helpful?

In each case there is a inflection point where higher tech is called for. But in all cases, the same effect can be achieved: a balanced account, an excellent vineyard.

And in all cases you have to actually pay attention to the accounts. And pay attention to the vineyard.

By: Bradley

Bradley — Sat, 14 Apr 2007 04:19:21 +0000

I’m on your side here, Josh.
Anything that allows me (not a farmer) to become a better farmer is a good thing when it comes to grapes. I love walking the vineyard and nuzzling the vines and stroking the buds and caressing the bunches but I don’t have x-ray eyes. Why not use a little technology if makes me a better steward of the land and, by extension, a better grower of grapes. Farmers don’t want risk; they get all the curveballs they can stand from nature. Time to put another ace up the sleeve I say. Can’t have enough friends in your corner.