Friday, February 13, 2009

Low Yield vs. High Yield

Generally, if one were to come upon this choice, the answer would be high yield and the topic would almost certainly relate to yields on CDs, Treasuries, or high grade Bonds. Yet, in the wine sphere, and particularly in the vineyard( and later in the barrel), low yielding vines have high yielding vines outclassed hands down, when it comes to caliber of, or quality of wine grapes. Don't get me wrong...there are grape growers out there who have land flat as a billiard table, machine hedge, machine pick, produce 10-12 Tons/ acre, and sell exclusively into the Japanese market. No one reading this blog would be interested, (even out of curiousity) what those grapes, and more importantly, what those wines tasted like. I could guess, but that just sends shivers up and down my spine.

More to the point, there still remain proponents of "There is no difference in grape tasting nor in wine tasting of yields of 3Tons/ acre vs yields of 5 Tons/ acre". Some stretch that to 6Tons rather than 5, and swear up and down that there is no difference. Well, maybe so, but in our vineyard I have experimented with 5 Tons/acre vs 3Tons, 2.5Tons, and 1 Ton/acre yields;
and I can tell you that only somebody with burned out taste buds would make the assertion that 3 Ton yields make no better wines than 5 Ton yields. That is just patently absurd, but that doesn't mean there isn't a coterie of folks out there who don't truly believe it. There is a difference between 3T/ acre and 2.5 Ton/acre, but it is, to my taste buds, ever so slight. 1Ton/acre is certainly better yet, but not three times is just better. Unfortunately, it is also economically not feasible unless a vineyard is planted 23oo vines/ acre or as many as 4000 vines/acre. Once you start doing that tho, special equipment is necessary, again neatly overly priced, and pretty soon only a multi-millionaire could afford to farm that kind of operation.

Back to reality, most vineyards are planted somewhere between 870 vines/acre and 740 vines/acre(spacing of 5'X 10' and 5'X 12' , respectively). A 3Ton/acre vineyard on 5'x 10' planting means about 6 lbs of grapes/vine; our Cab averages .3 lbs/cluster and 8 to 10 spurs/vine, with 2 shoots/ spur. Allow 1 cluster/shoot, and you should have somewhere between
16 to 20 clusters/vine. Allowing for dropping any cluster that touches another, we end up somewhere between 4.8 and 6.0 lbs/vine. This spacing allows air to circulate in and thru the entire cluster, as well as allowing maximal amount of light to all parts of the cluster. These two issues can determine whether a cluster ripens fully thru and thru, vs just ripening on the outer portion of the cluster. Also consider that where air and light can get to and thru a cluster, one will need less fungicide or pesticide, because dense, damp, unlit areas do not occur(or certainly occur less frequently) for these unencumbered clusters.

Now imagine 5-6 Tons/acre vines, still with 5'X10' spacing, and what you have is twice as many clusters in the same space, with cluster overlap, poor venting of air around the cluster, and a large portion of the outer cluster that never sees the light of day. Immediately the chance of mildew or mold goes up, the need for fungicides increases, and the chance of all these grapes ripening anywhere nearly as well as vines with half that load, is slim at best. To me this pretty well ends the argument, and tasting grapes as well as the wines from each lot, confirms it.

5Ton/acre wines will taste herbaceous, or green, if you will, and should you like your wine to taste like green peppers, or salad, then this is the choice for you. Additionally, the tannins in Cab grown thus will be harsh and distasteful. What's really interesting, is that there are vineyard consultants out there advising growers, who are wedded to the idea if 3 Tons/ acre is good, then 5 Tons/ acre is better. I have had this conversation with many grape growers, and it is not one I can easily win. After all, 5 Tons/acre makes more money than 3Tons/acre, so the farmer sees it as thus.

Here, I lay some of the blame for higher yielding vineyards squarely on the doorstep of wineries. If they want high end wines, they necessarily should be using low yield grapes. A high foot traffic location can convince a vintner he can skate with 5-6Ton/ acre grapes, and still sell a lot of wine. Frankly, this is a black eye for the wine industry, grape farmers and vintners both. It is a practice which can lower the AVA's reputation for producing excellent wines and grapes. Oddly, some wineries still do not subscribe to low yields equal excellent wines equation, but sooner or later someone is going to tell those folks that "the emperor is wearing no clothes".

So, "low yields equal great wines" is the way to go with respect to crop loads, but that assumes everything else is equal and is done in the proper fashion. "A great wine starts in the vineyard", is a very old mantra, and crop loads play a large part of that. Nonetheless, terroir, individual vine attention, proper nutrition of vines, water needs, climatic conditions, hang time...there are more, many more considerations in making a great wine. Simple truths still hold true. Paying attention to them is essential for every vintner. As the years roll by, I firmly believe the high yield theory will relate to CDs and bonds...not crop loads for grapes and fine wines.

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