Training systems and pruning practices at the Masseto (Bolgheri, Tuscany) vineyard

Masseto is one of the the world's leading Merlot wines and its 6.63 ha vineyard is ensconced within the confines of the larger Ornellaia vineyard in Bolgheri, Tuscany.

It has been difficult to obtain information on the details of this vineyard so I have undertaken the task of deconstructing it using data from publicly available sources as well as reasoned assumptions. In this post I cover training systems and pruning practices.

According to the Article 4 rules of the Bolgheri DOC (Bolgheridoc.com):

• Vineyard layouts, training systems, and pruning practices must be those in general use in the area and in any case such as will not change the characteristics of either grapes or wine. Expansive training systems are not allowed.
• All vineyards planted after 21 March 2011 shall have a density of at least 4500 vines per ha calculated according to a vineyard with a maximum of 2.5 meters between vine rows.

Clay soils have an infiltration rate of .5 mm/hour, the slowest of all soil types. Vines planted in linked terraces have a runoff rate of .72 g/l while vines planted with the slope allow runoffs of 4.18 g/l. Given these variables, Masseto has opted for a vineyard layout that is perpendicular to the slope in order to allow the summer rains to percolate slowly into the soil rather than to run off vertically.

According to Paul Domoto (Constructing a vineyard trellis, Presentation at the Iowa Grape Growers Conference, 1/26/02), a vineyard trellis serves as a framework for training and supporting the vines and should be:

• Strong enough to support large crops and withstand high winds
• Able to last 20 or more years with routine maintenance.

Based on images from the Masseto vineyard, as well as other vineyards in the area, my perception is that the trellis construct of choice is an anchored end-post system with earth anchor. The longevity of this construct will be enhanced by pressure treating the posts with chromated copper arsenate.

Anchored end-post system (Source: Bernd Meyer, Trellis End
Post Assembly Designs for Vineyards, aces.nmsu.edu)

According to masseto.com, the Masseto vine planting density is 3.0 x 0.85.

The predominant cordon system in Bolgheri is cordon spur but there are also examples of guyot and gobelet.  Some viticulturists avoid the guyot system because of its increased growth on the outer edges of the plant and the additional work required to keep the vine in balance. In addition, Guyot is designed for low-to-moderate-vigor vineyards (Patty Skinkers, Guyot vine training system, Oregon State University, extension.org). Vigorous vines - a la Masseto -- are not suited to the guyot system because of “high shoot density and inner canopy shading” which reduces leaf surface area exposure. Masseto trains according to the unilateral cordon spur system.

The goal of canopy management is to provide a properly balanced vine with the right ratio of shoots to leaves and the “right” fruit exposure to light (Cliff Ohmart, The science behind canopy management, winesandvines.com, November 2009). Vine balance is affected by the trellis, spacing, pruning, irrigation, nutrition program, rootstock, and scion as well as the vineyard site and the regional climate (Ohmart). The canopy management strategy of choice is two leaf layers in the vine to (i) allow “good exposure to the leaves so that they are fully active and (ii) to provide light through the canopy to the fruit.” The canopy will be managed through pruning during the vegetative cycle and leaf removal during the summer period. Other practices such as hedging and the use of cover crops to provide competition could be utilized. Masseto prunes 5% - 10% of the production "to help the vines reach their optimum equilibrium" (masseto.com).

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