3.1.3.b Defining a daily harvesting rhythm

Based on past practices and experience

There are several ways of approaching the daily harvesting rhythm:

• One that takes into account the number of employees present and available and then adapts the daily volume to be harvested accordingly

• One that takes into account the number of employees but first sets the daily harvesting volume and then adjusts the number of employees needed to maintain this rhythm.

At Château Latour, this second method is applied. For example, on close vines trained at 1m, an area of 1 to 1.5 ha depending on the quantity of grapes will require the mobilization of about 20 people working a 7-hour day. Sometimes it is more useful to consider the tonnage harvested per day rather than the surface area. It appears that a picker can harvest 800 to 1000 kg of grapes in one day of work on unthinned vines. In this way, if the forecasted daily volume established is 40 tons (40,000 kg), about 50 people will be needed. When two geographically distant plots of land are planned on the same day, these 50 people can form two different teams.

Providing a safety margin: take into account possible constraints

• The weather: extreme conditions (rain, heatwaves) can be difficult for the harvesters to tolerate; this is the first constraint.

• The plot's topography: a plot that is difficult to access, with a steep slope, requires more time.

• The grape yield: this will also influence the harvesting speed. If the yields are high, more time may be needed for the plot. In such cases, it may be more reasonable to count tons of grapes per day rather than ha per day.

• The health of the vines: vines whose health has been compromised will require more time during the harvest, when an initial sorting in the vineyard is carried out for example. Some severe attacks of fungi, such as mildew, cause the drying of whole bunches of grapes, sometimes resulting in significant harvest losses.

• The harvesting team: speed will inevitably vary depending on the size of the teams and the number of teams.

• Finally, yield estimates may be slightly off. It is possible to obtain lower or higher volumes of grapes than expected, in which case adaptation will be necessary in the winery. Using the example of 40 tons harvested in one day, it is prudent to plan for a capacity of 400 hl for an estimated 380 hl.

It is necessary to take all of these factors into consideration when calculating the surface area or the volume that one wishes to harvest per day.